זמנים
הלכות חמץ ומצה
פרק א

Halacha

הלכה א
כָּל הָאוֹכֵל כְּזַיִת חָמֵץ בְּפֶסַח מִתְּחִלַּת לֵיל חֲמִשָּׁה עָשָׂר עַד סוֹף יוֹם אֶחָד וְעֶשְׂרִים בְּנִיסָן בְּמֵזִיד חַיָּב כָּרֵת שֶׁנֶּאֱמַר (שמות יב טו) "כִּי כָּל אֹכֵל חָמֵץ וְנִכְרְתָה". בְּשׁוֹגֵג חַיָּב קָרְבַּן חַטָּאת קְבוּעָה. אֶחָד הָאוֹכֵל וְאֶחָד הַמְמַחֶה וְשׁוֹתֶה:
כסף משנה
1.
Anyone who intentionally eats an olive's size1Whenever the Torah uses the verb אכל (eat) in the context of a mitzvah or a prohibition, it refers to the consumption of at least a minimum amount, established by Eruvin 4b as the size of an olive.
It must be emphasized that the measure of a כזית (an olive's size) cannot be determined by measuring an average olive today. Rather, it is dependent on the measure established by the Sages and this is the subject of debate by the Rabbinic authorities. The Pri Chadash (Orach Chayim 486) explains that the Rambam considers an olive as one third the size of an egg (כביצה, a more familiar Talmudic measure). In terms of modern measurements, this olive size would be between 16.6 and 24 grams, according to various Halachic opinions.
Tosefot (Chullin 103a) differs, and defines a כזית(the size of an olive) as one half the size of an egg (between 25.6 and 36 grams according to the various opinions). With regard to the practical application of the law (halachah l'ma'aseh), the Shulchan Aruch HaRav (Orach Chayim 486) advises that in all questions of Torah law, Tosefot's opinion should be followed. However, in questions of Rabbinic law, the more lenient opinion can be relied upon.
[כזית, or more]2Eating less than this amount of chametz is also forbidden by Torah law. However, there is no punishment for its consumption, nor need a sacrifice be brought as atonement (See Halachah 7). of chametz3any mixture made from grain or grain products that has come into contact with water and was allowed to become leavened. The following (and only the following) five species are referred to as grain: wheat, rye, barley, oats, spelt. on Pesach from the beginning of the night of the fifteenth [of Nisan] until the conclusion of the day of the twenty-first [of Nisan]4In the mitzvot mentioned above, the Rambam also mentions the prohibition against eating chametz from noon on the fourteenth of Nisan. However, the violation of that prohibition is not punishable by כרת. is liable for כרת,5The prohibition against eating chametz on Pesach is counted as one of the 613 mitzvot of the Torah. See Sefer HaMitzvot, negative commandment 197; Sefer HaChinuch, mitzvah 19. as [Exodus 12:15] states: "Whoever eats leaven... will have his soul cut off."6Moed Kattan 28a relates that a person who violated a sin punishable by כרת would die before reaching the age of fifty.
In his commentary on the Mishnah, Sanhedrin 9:6, the Rambam emphasizes that premature death does not represent the totality of the retribution these individuals will receive. In addition, "their souls will be cut off."
In Hilchot Teshuvah 8:1, the Rambam elaborates on the latter dimension:
The good that is hidden for the righteous is the life of the world to come... The retribution of the wicked is that they will not merit this life. Rather, they will be cut off and die.
This is the intent of the meaning of the term כרת in the Torah, as [Numbers 15:31] states: "That soul shall surely be cut off."

[Should one eat this amount of chametz] unintentionally,7בשוגג one is liable to bring a fixed sin offering8The Rambam adds the word "fixed" to indicate that he is referring to the standard sin offering described in Leviticus 4:27-35, in contrast to the offering to atone for certain sins mentioned in Leviticus, Chapter 5. (See Hilchot Shegagot 1:3.) The latter offering is not "fixed," but rather is adjustable according to the financial state of the person liable. [as atonement].
[The above applies] equally to one who eats chametz and one who converts it into a liquid and drinks it.9Though the Torah specifically mentions "eating," Chullin 120a equates drinking a liquid made from chametz and water with the former act. In his responsum (Vol. V, 1517), the Radbaz differentiates between mixing chametz with water (the instance in question here) and mixing chametz with other substances, as mentioned in Halachah 6. The punishment of כרת applies only when nothing else but chametz and water is contained in the mixture.

הלכה ב
הֶחָמֵץ בַּפֶּסַח אָסוּר בַּהֲנָיָה שֶׁנֶּאֱמַר (שמות יג ג) "לֹא יֵאָכֵל חָמֵץ" לֹא יְהֵא בּוֹ הֶתֵּר אֲכִילָה. וְהַמַּנִּיחַ חָמֵץ בִּרְשׁוּתוֹ בְּפֶסַח אַף עַל פִּי שֶׁלֹּא אֲכָלוֹ עוֹבֵר בִּשְׁנֵי לָאוִין שֶׁנֶּאֱמַר (שמות יג ז) (דברים טז ד) "לֹא יֵרָאֶה לְךָ שְׂאֹר בְּכָל גְּבֻלֶךָ" וְנֶאֱמַר (שמות יב יט) "שְׂאֹר לֹא יִמָּצֵא בְּבָתֵּיכֶם". וְאִסּוּר הֶחָמֵץ וְאִסּוּר הַשְּׂאוֹר שֶׁבּוֹ מַחְמִיצִין אֶחָד הוּא:
כסף משנה
2.
On Pesach, it is forbidden to derive any benefit from chametz,1for example, to sell it or use it for purposes other than eating. as [Exodus 13:3] states: "Do not eat (לא יאכל) chametz"; i.e., it is not permitted [to be used to derive benefit that leads to]2The bracketed additions are based on Rashi's commentary on Pesachim 21b. eating.3The Rambam's statements are somewhat problematic. Pesachim 21b records the following disagreement between the Sages:
Chizkiyah states: What is the source from which we learn that it is forbidden to derive benefit from chametz? [Exodus 13:3] states: "Do not eat (לא יאכל) chametz"; i.e., it is not permitted [to be used to derive benefit that leads to] eating.
His decision is based on the fact that the Torah uses the expression לא יאכל. Had the Torah not written יאכל לא, we may presume that a prohibition against eating would be implied, but not a prohibition against deriving benefit.
This contradicts the opinion of R. Abahu who states: Wherever the Torah states לא תאכל, לא יאכלor לא תאכלו, a prohibition against eating and deriving benefit is implied.
The Rambam's statements in this Halachah quote the opinion of Chizkiyah. However, in Hilchot Ma'achalot Asurot 8:15, he quotes the opinion of R. Abahu as accepted halachah.
The Kessef Mishneh resolves the contradiction, explaining that in the halachah at hand, there is no difference in law between Chizkiyah and R. Abahu. Therefore, although the Rambam generally accepts R. Abahu's opinion, in this instance he quotes Chizkiyah's statements because the manner in which the latter derives the concept is more explicit.

A person who leaves chametz within his property on Pesach,4As stated in Halachah 9, once chametz becomes forbidden on noon of the fourteenth of Nisan, we may not derive any benefit from it. even though he does not eat it, transgresses two prohibitions: [Exodus 13:7] states: "No leavening agent may be seen in all your territory"5This prohibition is counted as one of the 613 mitzvot of the Torah: Sefer HaMitzvot, negative commandment 200; Sefer HaChinuch, mitzvah 20. and [Exodus 12:19] states: "No leavening agent may be found in your homes."6This prohibition is counted as one of the 613 mitzvot of the Torah: Sefer HaMitzvot, negative commandment 201; Sefer HaChinuch, mitzvah 11.
[Though the prohibitions stated in these verses apply to שאור,]7S'or refers to leavening agents, notably yeast. it is the same prohibition which forbids both חמץ (leaven) and שאור (a leavening agent).8Beitzah 7a explains that Exodus 13:7 mentions both chametz (leaven), and שעור (S'or, a leavening agent) in the same verse to emphasize that they are identical.
The Ra'avad comments that the equation between the prohibitions against chametz and S'or is not complete. Among the differences between them are: Once chametz is no longer fit to be eaten by a dog, it is no longer prohibited. In contrast, yeast is never fit to be eaten and is prohibited even in that state. Nevertheless, the Maggid Mishneh and the Kessef Mishneh do not accept his statements.

הלכה ג
אֵינוֹ לוֹקֶה מִשּׁוּם לֹא יֵרָאֶה וְ(שמות יב יט) "לֹא יִמָּצֵא" אֶלָּא אִם כֵּן קָנָה חָמֵץ בְּפֶסַח אוֹ חִמְצוֹ כְּדֵי שֶׁיַּעֲשֶׂה בּוֹ מַעֲשֶׂה. אֲבָל אִם הָיָה לוֹ חָמֵץ קֹדֶם הַפֶּסַח וּבָא הַפֶּסַח וְלֹא בִּעֲרוֹ אֶלָּא הִנִּיחוֹ בִּרְשׁוּתוֹ אַף עַל פִּי שֶׁעָבַר עַל שְׁנֵי לָאוִין אֵינוֹ לוֹקֶה מִן הַתּוֹרָה מִפְּנֵי שֶׁלֹּא עָשָׂה בּוֹ מַעֲשֶׂה. וּמַכִּין אוֹתוֹ מַכַּת מַרְדּוּת:
כסף משנה
3.
[A violator] is not lashed1this is the punishment given for the active violation of any of the Torah's prohibitions that are not punishable by death. for [transgressing the prohibitions] not to have [chametz] seen [in his possession] and not to have [chametz] found [in his possession] unless he purchased chametz on Pesach2The Tzafnat Paneach emphasizes that this law applies only to chametz purchased from a gentile. However, once chametz belonging to a Jew becomes prohibited, that Jew no longer has the authority to sell it. Thus, the purchaser will never really become the legal owner of the chametz (See Rashi, Sukkah 35a; Tosefot, Chullin 4b).
The Or Sameach questions how a person can become liable even for chametz purchased from a gentile, but resolves the issue based on the commentary of Rabbenu Nissim (Avodah Zarah, Chapter 3).
or [caused flour] to become leavened, and thus committed a deed.3The Mishneh LaMelech raises a significant question: A person is not liable for lashes for violating any prohibition which he can correct by fulfilling a positive commandment (לעשה לאו הניתק): For example, if a person violates the prohibition against taking both a mother bird and her eggs, he can free himself from the punishment of lashes by sending away the mother bird.
Tosefot (Pesachim 29b) states that the prohibition against chametz being seen in one's property falls into the above category, because one can correct the violation of this prohibition by fulfilling the positive commandment to destroy chametz. Thus, it appears that a person can never be held liable for lashes for this transgression.
Among the resolutions offered to this difficulty is that of Rav Chayim Soloveitchik, who explains that Tosefot's statements apply only according to the opinion of Rabbi Yehudah, who maintains that chametz must be destroyed by burning. However, according to the Sages (whose opinion is accepted by the Rambam, Halachah 3:11), who maintain that chametz can be destroyed by any means, not necessarily burning, the prohibition against possessing chametz is not considered a לאו הניתק לעשה.
What is the essential difference between these opinions: Rabbi Yehudah maintains that the fundamental aspect of the mitzvah to destroy chametz revolves upon the article itself (חפצה); it is a mitzvah to destroy chametz. In contrast, the Sages maintain that the mitzvah centers on the person (גברה); he is commanded to remove all chametz from his possession.
According to Rabbi Yehudah, since the commandment revolves around the chametz itself, its destruction directly "corrects" the sin of its possession. In contrast, according to the Sages, the positive commandment of ridding one's house of chametz is merely a reinforcement of the prohibition against its possession, and the fulfillment of the positive commandment does not have the power to "correct" the violation of the prohibition.

However, if he possessed chametz before Pesach, and when Pesach came he did not destroy it and left it in his possession,4However, should he remove it from his possession (by giving it to another person or declaring it ownerless), he is not liable even if he does not actually destroy the object. even though he transgresses two prohibitions, according to the Torah, he is not lashed, for he did not perform a deed.5Sh'vuot 21b states: "The transgression of any prohibition which does not involve a deed is not punishable by lashing." [Nevertheless,] he is given "stripes for being rebellious."6"Stripes for being rebellious (מכות מרדות)" is a punishment instituted by the Sages for violation of a Rabbinic prohibition. A person liable for lashing according to Torah law receives a uniform number of 39 lashes unless he is physically incapable of bearing that number. In contrast, the number of lashes given to a person liable for "stripes for being rebellious" is left to the discretion of the court.
Chullin 14b states that this punishment is also inflicted upon those who violate a Torah prohibition that is not punishable by lashing.

הלכה ד
חָמֵץ שֶׁעָבַר עָלָיו הַפֶּסַח אָסוּר בַּהֲנָיָה לְעוֹלָם. וְדָבָר זֶה קְנָס הוּא מִדִּבְרֵי סוֹפְרִים מִפְּנֵי שֶׁעָבַר עַל בַּל יֵרָאֶה וּבַל יִמָּצֵא אֲסָרוּהוּ. אֲפִלּוּ הִנִּיחוֹ בִּשְׁגָגָה אוֹ בְּאֹנֶס. כְּדֵי שֶׁלֹּא יַנִּיחַ אָדָם חָמֵץ בִּרְשׁוּתוֹ בְּפֶסַח כְּדֵי שֶׁיֵּהָנֶה בּוֹ אַחַר הַפֶּסַח:
כסף משנה
4.
It is prohibited to ever benefit from chametz1itself, in contrast to mixtures of chametz, as explained in Halachah 5. [that a Jew]2in contrast to a gentile (Pesachim 28a). possessed during Pesach.3This prohibition applies to all Jews, not only to the owner of the chametz (Rabbenu Nissim, Pesachim 28). Thus, it is prohibited to buy chametz from a store owned by a Jew who did not observe the prohibition against possessing chametz on Pesach. This prohibition is a penalty instituted by the Sages.4Pesachim 29a mentions Rabbi Yehudah's opinion that the prohibition stems from the Torah itself. However, this opinion is not accepted as halachah.
The Tzafnat Paneach explains that the debate between Rabbi Yehudah and Rabbi Shimon (who maintains that the Torah does not forbid benefiting from chametz after Pesach) revolves around an abstract concept. Rabbi Yehudah maintains that once Pesach comes, chametz itself becomes forbidden and, therefore, can never become permitted again. In contrast, Rabbi Shimon maintains that the prohibition does not affect the essence of the chametz itself. Thus, we are forbidden to benefit from it during Pesach, but after Pesach there is no prohibition.
Since the person transgressed [the prohibitions against chametz] being found and being seen [in his possession], they prohibited its use.5The Maggid Mishneh explains that the prohibition against using a Jew's chametz after Pesach applies even when the prohibitions against possessing chametz are not violated. See Halachah 4:5.
[The above applies] even if he inadvertently left [the chametz in his possession during Pesach]6e.g., he forgot that he possessed it. or was forced to do so.7The Nodah BiYhudah (Orach Chayim 20) gives an example of such a case. A thief stole chametz from a person before Pesach and returned it to him after the holiday. Even though the person had no opportunity to destroy it before Pesach, it is forbidden.
In that responsum, the Nodah BiYhudah also raises the following question: A person died on the fourteenth of Nisan without nullifying or selling his chametz. Are his heirs forbidden to benefit from that chametz or not? He maintains that although the Rambam would probably prohibit benefiting from this chametz, there are rationales on the basis of which its use may be permitted. [Other authorities (note Shulchan Aruch HaRav, Kuntres Acharon 435) do not accept this conclusion.]
[These stringencies were instituted] lest a person8intentionally leave chametz in his possession during Pesach in order to benefit from it after Pesach.9on the pretense that he had forgotten about its existence.

הלכה ה
חָמֵץ שֶׁנִּתְעָרֵב בְּדָבָר אַחֵר תּוֹךְ הַפֶּסַח בֵּין בְּמִינוֹ בֵּין שֶׁלֹּא בְּמִינוֹ הֲרֵי זֶה אוֹסֵר בְּכָל שֶׁהוּא. וְחָמֵץ שֶׁל יִשְׂרָאֵל שֶׁעָבַר עָלָיו הַפֶּסַח אַף עַל פִּי שֶׁהוּא אָסוּר בַּהֲנָיָה אִם נִתְעָרֵב בֵּין בְּמִינוֹ בֵּין שֶׁלֹּא בְּמִינוֹ הֲרֵי זֶה מֻתָּר לְאָכְלוֹ אַחַר הַפֶּסַח. שֶׁלֹּא קָנְסוּ וְאָסְרוּ אֶלָּא בֶּחָמֵץ עַצְמוֹ אֲבָל הַתַּעֲרֹבֶת מֻתָּר בַּאֲכִילָה לְאַחַר הַפֶּסַח:
כסף משנה
5.
If, on Pesach,1Rabbenu Asher and the Sefer Mitzvot Gadol maintain that this principle does not apply until the holiday itself actually begins. Thus, even if chametz became mixed with other substances on the fourteenth of Nisan, after the time chametz is forbidden, the mixture is bound by the laws regarding the nullification of forbidden objects (ביטול איסורים) that apply throughout the entire year.
The Kessef Mishneh maintains that a simple interpretation of the Rambam's statements leads to the conclusion that he accepts this opinion. Though others, among them the Maggid Mishneh, do not accept this view, it is accepted as Halachah (Shulchan Aruch, Orach Chayim 447:2).
even the slightest amount of chametz becomes mixed together with another substance,2Ordinarily, it is permissible to use a mixture of a prohibited substance and a permitted substance provided that the permitted substance is present in a greater amount, to the extent that the prohibition is nullified (ביטול איסור). either of its kind3When the prohibited substance is of the same kind as the forbidden substance (e.g., improperly slaughtered meat mixed with properly slaughtered meat), all that is required to nullify the prohibition is that the permitted substance constitutes the majority of the mixture (Hilchot Ma'achalot Asurot 15:1). or not of its kind,4When the prohibited substance is of a different kind from the permitted (e.g., forbidden fats mixed with grain), the prohibition is ordinarily nullified if the taste of the forbidden article is not discernible, or the quantity of the permitted substance is at least 60 times as great as the forbidden article (ibid. 15:1, 6). [the entire mixture] is forbidden.5The above principles do not apply with regard to chametz on Pesach. Even the slightest mixture of chametz may not be eaten, nor may benefit be derived from it. In Hilchot Ma'achalot Asurot (15:9), the Rambam explains that this stringency is instituted because chametz is a דבר שיש לו מתירין (a substance which later will become permitted).
A דבר שיש לו מתירין which becomes mixed together with a permitted substance of its own kind is never permitted to be used because of the following rationale: Since its use in its entirety will later become permitted, there is no need to grant a leniency allowing it to be eaten when forbidden.
Similarly, with regard to chametz on Pesach: There is no prohibition against using a mixture of chametz after Pesach. Hence, there is no need to grant permission to eat such a mixture on Pesach itself, even though the quantity of the permitted substance far surpasses that of the chametz.
Furthermore, there is a stricter dimension to chametz than to any other דבר שיש לו מתירין. Generally, a דבר שיש לו מתירין is permitted if it becomes mixed with a substance of another kind to the extent that its taste can no longer be discerned. However, this leniency is not granted regarding mixtures of chametz. Since Exodus 12:20 states: "You must not eat any leaven," the severity of the prohibition obligates additional stringency.

Though it is forbidden to benefit from chametz which a Jew possessed on Pesach, if it became mixed with another substance, whether of its kind6for example, a dough containing yeast mixed with flour. or not of its kind,7for example, a mixture of flour with any other substance. it is permitted to be eaten after Pesach.8The Ma'aseh Rokeach explains that this leniency applies whether the mixture occurred after Pesach or on the holiday itself. Nevertheless, the latter point should not be misinterpreted. Should such a mixture be discovered on Pesach, we are obligated to destroy it (Ramah, Orach Chayim 447:1). Nevertheless, if either intentionally or unintentionally, the mixture was not destroyed on the holiday itself, it may be used afterwards. [The Sages] only penalized and forbade [the use of] chametz itself. A mixture [containing chametz possessed on Pesach] is permitted to be eaten after Pesach.9Pesachim 30a explains that since the penalty is of Rabbinic origin, it was applied only to chametz itself and not to mixtures.

הלכה ו
אֵין חַיָּבִין כָּרֵת אֶלָּא עַל אֲכִילַת עַצְמוֹ שֶׁל חָמֵץ אֲבָל עֵרוּב חָמֵץ כְּגוֹן כּוּתָח הַבַּבְלִי וְשֵׁכָר הַמָּדִי וְכָל הַדּוֹמֶה לָהֶן מִדְּבָרִים שֶׁהֶחָמֵץ מְעֹרָב בָּהֶן אִם אֲכָלָן בְּפֶסַח לוֹקֶה וְאֵין בּוֹ כָּרֵת שֶׁנֶּאֱמַר (שמות יב כ) "כָּל מַחְמֶצֶת לֹא תֹאכֵלוּ". בַּמֶּה דְּבָרִים אֲמוּרִים בְּשֶׁאָכַל כְּזַיִת חָמֵץ בְּתוֹךְ הַתַּעֲרֹבֶת בִּכְדֵי אֲכִילַת שָׁלֹשׁ בֵּיצִים הוּא שֶׁלּוֹקֶה מִן הַתּוֹרָה. אֲבָל אִם אֵין בַּתַּעֲרֹבֶת כְּזַיִת בִּכְדֵי אֲכִילַת שָׁלֹשׁ בֵּיצִים אַף עַל פִּי שֶׁאָסוּר לוֹ לֶאֱכל אִם אָכַל אֵינוֹ לוֹקֶה אֶלָּא מַכִּין אוֹתוֹ מַכַּת מַרְדּוּת:
כסף משנה
6.
One is liable for כרת1as stated in Halachah 1 only for eating chametz itself. However, a person who eats a mixture containing chametz—for example, Babylonian kotach,2a mixture including sour milk, moldy bread crusts, and mineral salts (Pesachim 42a). Median beer,3beer made of fermented barley, as our beer. Generally, the beer referred to in the Talmud was made from fermented dates (Rashi, Pesachim 42b). or similar mixtures which contain chametz--[is4Pesachim 42a also emphasizes that a person transgresses the commandments against possessing chametz if he owns any of the above mixtures. punished by] lashes and is not liable for כרת [for this involves the transgression of a different commandment],5different from eating chametz itself as [Exodus 12:20] states: "Do not eat any leaven."
When6The Sefer HaMitzvot (negative commandment 198) and the Sefer HaChinuch (mitzvah 12) consider this as one of the Torah's 613 commandments.
Nevertheless, this decision is a matter of debate among the commentators. The Ramban (Hasagot to Sefer HaMitzvot) does not accept the Rambam's view, and explains that a person who consumes an olive size of chametz within the specific time period (פרס כדי אכילת) described below should be liable for כרת as described in Halachah 1. See also Halachah 4:8 and commentary.
The Maggid Mishneh supports the Ramban's view, noting that in Hilchot Ma'achalot Asurot 15:3, the Rambam himself explains that any person who eats a mixture containing an olive size of a forbidden food within this time period is liable, just as if he had eaten the forbidden food itself.
Based on the explanation of the Tur (Orach Chayim 442), the Drisha and the Pri Chadash interpret the Rambam as referring to a mixture to which the chametz does not impart any flavor and is added only for consistency and color.
The Tzafnat Paneach offers a different interpretation, explaining that were chametz to be mixed with other foods, a person eating the mixture would be liable for כרת as the Ramban states. However, the Rambam is talking about an instance when flour was mixed with another substance and became leavened as part of the mixture, without ever becoming a distinct entity of its own. The Torah considers this as a different category of chametz and holds a person who eats it liable for a lesser punishment.
does the above apply? When the person consumed an olive size7the minimum size of a prohibited substance for which one is liable for punishment, as explained in Halachah 1. of chametz [while eating] from the mixture within the time it takes to eat three eggs or less.8This period (כדי אכילת פרס in Hebrew) is significant in halachah. Just as the Torah requires a specific quantity, the size of an olive, as regards many of the mitzvot and prohibitions concerning eating, it also specifies a limited period in which this amount of food must be consumed: אבילת פרס כדי.
This measure is also a point of Rabbinic controversy. The Rambam defines it as the time it takes to eat three eggs (Hilchot Ma'achalot Asurot 14:8). Rashi (Pesachim 44a) takes a more lenient view, defining it as the amount of time it takes to eat four eggs. As regards this matter as well, the Shulchan Aruch HaRav (Orach Chayim 612:4) advises that whenever a question of Torah law is involved, the more stringent opinion should be observed. However, in questions of Rabbinic law, the more lenient view can be relied on.
In converting this figure to modern measures of time, there is also a difference of opinion. The shortest opinion limits this period to two minutes. The most commonly accepted view is four minutes and there are opinions of seven and eight minutes as well.
Then, he is obligated for lashes by the Torah.9as explained above. However, if he does not consume an olive size of chametz from the mixture in less time than it takes to eat three eggs, even though such eating is forbidden,10for as explained in the previous halachah, chametz can never be nullified within a mixture. As the following halachah explains, eating less than an olive size of chametz is also prohibited by Torah law. Nevertheless, he is not [punished by] lashing. Rather, he is given "stripes for being rebellious."11see Halachah 3.

הלכה ז
הָאוֹכֵל מִן הֶחָמֵץ עַצְמוֹ בְּפֶסַח כָּל שֶׁהוּא הֲרֵי זֶה אָסוּר מִן הַתּוֹרָה שֶׁנֶּאֱמַר (שמות יג ג) "לֹא יֵאָכֵל". וְאַף עַל פִּי כֵן אֵינוֹ חַיָּב כָּרֵת אוֹ קָרְבָּן אֶלָּא עַל כַּשִּׁעוּר שֶׁהוּא כְּזַיִת. וְהָאוֹכֵל פָּחוֹת מִכְּזַיִת בְּמֵזִיד מַכִּין אוֹתוֹ מַכַּת מַרְדּוּת:
כסף משנה
7.
Eating even the slightest amount of chametz itself1The laws regarding mixtures of chametz were mentioned in the previous halachah. on Pesach is forbidden by the Torah2The commentaries cite the source for the Rambam's decision as Yoma 73b, which mentions Rabbi Yochanan's opinion that all the Torah's prohibitions against eating apply even when one consumes less than the size of an olive (חצי שיעור), that measure being significant only as regards punishment. as [Exodus 13:3] states: "Do not eat [leaven]."3The Kessef Mishneh questions why the Rambam cites this verse. Yoma (ibid.) derives the prohibition against eating less than an olive size of prohibited substances from another source.
The Radbaz (Responsa, Vol. V, 143) explains that the prohibition against חצי שיעור exists only when eating the prohibited substance itself. In contrast, חצי שיעור of chametz is forbidden even when mixed with other substances, as explained in the previous halachah. He explains that since deriving benefit from chametz is forbidden according to Torah law, that prohibition also includes eating חצי שיעור in any form.
Nevertheless, [a person who eats chametz] is not liable for כרת, nor must he bring a sacrifice for anything less than the specified measure, which is the size of an olive.4Nevertheless, [a person who eats chametz] is not liable for
כרת
5as stated in Halachah 1.
A person who intentionally violates the prohibition and eats less than an olive size of chametz6The Kessef Mishneh questions why the Rambam begins the halachah by describing the prohibition against "even the slightest amount" of chametz, and concludes with the expression "less than the size of an olive." is given "stripes for being rebellious."7Hilchot Ma'achalot Asurot 8:16 states that anyone who benefits from forbidden substances receives "stripes for being rebellious." A person who eats less than the size of an olive of chametz also benefits, and hence is liable for this punishment.

הלכה ח
אָסוּר לֶאֱכל חָמֵץ בְּיוֹם אַרְבָּעָה עָשָׂר מֵחֲצוֹת הַיּוֹם וּלְמַעְלָה שֶׁהוּא מִתְּחִלַּת שָׁעָה שְׁבִיעִית בַּיּוֹם. וְכָל הָאוֹכֵל בַּזְּמַן הַזֶּה לוֹקֶה מִן הַתּוֹרָה שֶׁנֶּאֱמַר (דברים טז ג) "לֹא תֹאכַל עָלָיו חָמֵץ". כְּלוֹמַר עַל קָרְבַּן הַפֶּסַח. כָּךְ לָמְדוּ מִפִּי הַשְּׁמוּעָה בְּפֵרוּשׁ דָּבָר זֶה לֹא תֹּאכַל חָמֵץ מִשָּׁעָה שֶׁרְאוּיָה לִשְׁחִיטַת הַפֶּסַח שֶׁהוּא (שמות יב ו) "בֵּין הָעַרְבַּיִם" וְהוּא חֲצִי הַיּוֹם:
כסף משנה
8.
It is forbidden to eat chametz on the day of the fourteenth [of Nisan] from noon onward—i.e.,1The Sefer HaMitzvot (negative commandment 199) and the Sefer HaChinuch (mitzvah 485) count this as one of the 613 mitzvot of the Torah. The Ramban and the Ra'avad take issue with this point, explaining that from noon on the fourteenth of Nisan until the beginning of the fifteenth at nightfall, there is a positive commandment to rid one's house of chametz, but no negative command forbidding the possession or eating of chametz. from the beginning of the seventh hour of the day.2The intent of this expression is midday. However, in particular, the term needs elaboration: According to Torah law, a day begins at dawn (עלות השחר), the appearance of the first rays of sun, and ends when three stars appear (םיבכוכה תאצ, Berachot 2b). This period is divided into 12 and the resulting figure is referred to as one seasonal hour (שעה זמנית). [Other opinions consider the period to be divided into twelve as beginning at the appearance of the sun, נץ החמה, and ending at sunset.]
Thus, if dawn were at 5:09 AM and three stars appeared at 6:45 PM, each seasonal hour would be an hour and eight minutes, and the beginning of the seventh hour would be 11:57 AM.
Any person who eats chametz3The Rambam explicitly states that lashes are never given for violating prohibitions against benefiting from forbidden articles (Hilchot Ma'achalot Asurot 8:16). The Mishneh Lamelech (Hilchot Yesodai HaTorah 5:8) elaborates on this principle in detail. during this time is punished by lashes according to Torah law,4as opposed to the punishment of כרת for eating chametz within Pesach, as described in Halachah 1. as [Deuteronomy 16:3] states: "Do not eat any leaven with it "; i.e., together with the Paschal sacrifice.
Based on the oral5Pesachim 5a tradition, we received the interpretation of that statement as: Do not eat any chametz during the time which is fit to slaughter the Paschal sacrifice, that being the afternoon—i.e.,6i.e., after midday. -- The Paschal sacrifice could be offered from midday on the fourteenth of Nisan until sunset (Hilchot Korban Pesach 1:1).
The Paschal sacrifice should not be slaughtered before the daily afternoon sacrifice, which would never be offered before half an hour past midday. However, if, by mistake, the Pesach sacrifice was slaughtered before the afternoon sacrifice, but after midday, its offering may be completed, provided a person continues stirring its blood until the afternoon sacrifice is offered (ibid. 1:3).
after midday.

הלכה ט
וְאָסְרוּ חֲכָמִים לֶאֱכל חָמֵץ מִתְּחִלַּת שָׁעָה שִׁשִּׁית כְּדֵי שֶׁלֹּא יִגַּע בְּאִסּוּר תּוֹרָה. וּמִתְּחִלַּת שָׁעָה שִׁשִּׁית יִהְיֶה הֶחָמֵץ אָסוּר בַּאֲכִילָה וּבַהֲנָיָה כָּל שָׁעָה שִׁשִּׁית מִדִּבְרֵי סוֹפְרִים וּשְׁאָר הַיּוֹם מִשְּׁבִיעִית וּלְמַעְלָה מִן הַתּוֹרָה. שָׁעָה חֲמִישִׁית אֵין אוֹכְלִין בָּהּ חָמֵץ גְּזֵרָה מִשּׁוּם יוֹם הַמְעֻנָּן שֶׁמָּא יִטְעֶה בֵּין חֲמִישִׁית לְשִׁשִּׁית. וְאֵינוֹ אָסוּר בַּהֲנָיָה בְּשָׁעָה חֲמִישִׁית. לְפִיכָךְ תּוֹלִין בָּהּ תְּרוּמָה וְלֶחֶם תּוֹדָה וְכַיּוֹצֵא בָּהֶן מֵחָמֵץ שֶׁהוּא קֹדֶשׁ לֹא אוֹכְלִין וְלֹא שׂוֹרְפִין עַד שֶׁתַּגִּיעַ שָׁעָה שִׁשִּׁית וְשׂוֹרְפִין הַכּל:
כסף משנה
9.
The Sages forbade the eating of chametz from the beginning of the sixth hour in order to prevent infringement upon a Torah commandment.1This is one of the Rabbinic commandments instituted as a "fence" and safeguard to Torah law. Thus, from the beginning of the sixth hour,2This is also a "seasonal hour." Thus, if as stated above, dawn of the fourteenth of Nisan is 5:09 AM and three stars appear at 6:45 PM, the beginning of the sixth hour is 10:49. it is forbidden to eat or benefit from chametz, based on Rabbinic law. During the rest of the day, from the seventh hour on, eating chametz is forbidden because of the Torah law.3as stated in the previous halachah.
During the fifth hour of the day,4in the instance stated above from 9:41 until 10:49. we do not eat chametz, lest the day be cloudy and we err between the fifth and six hours.5In his commentary to the Mishnah (Pesachim 1:4), the Rambam explains that it is possible that a person may err in his estimation of the time by an hour and thus, transgress the Rabbinic prohibition against possessing chametz at the sixth hour.
In a Responsa, the Rambam replies to the following question: The passage in Pesachim which is the source for this halachah appears to imply that a person may make an error of over two hours. Indeed, Rav Yitzchak Alfasi states the matter as such in his halachot. If so, why did the Rambam alter the explanation of the law.
In a reply which reflects his overall purpose in the composition of the Mishneh Torah, the Rambam answers:I mentioned a mistake of an hour which is a common error because my intention in composing this text is to bring the matters closer to our understanding or what is general practice.
However, there is no prohibition against benefiting from chametz during the fifth hour.6Since the restriction against benefiting from chametz during the sixth hour is only Rabbinic in origin, the Sages did not feel it necessary to forbid benefiting from chametz for another hour because of the mere possibility of error.
Therefore, Terumah7a portion of grain given to the priests and the breads of the thanksgiving offering8A thanksgiving offering involves 40 loaves, ten of which are leavened (Hilchot Ma'aseh HaKorbanot 9:17-18). which are chametz are left in a tentative status because of their holiness.9The Torah refers to Terumah as קדש (sanctified). Similarly, the breads of the thanksgiving offering have a sacrificial status. Therefore, They are neither eaten10for the Sages did not desire to relax their prohibition against eating chametz. Nevertheless, the priests were allowed to benefit from chametz during this period, and hence could feed Terumah to their animals. nor burned11for it is forbidden to destroy sacred articles unless absolutely necessary. Therefore, Pesachim 13b explains that thanksgiving offerings were not brought on the fourteenth of Nisan. [This law is also relevant at present. From the fourteenth of Nisan until the conclusion of Pesach, the "Psalm of Thanksgiving" is omitted from the morning service.] until the beginning of the sixth hour. Then, the entire quantity [of chametz] is burned.12because of the Rabbinic prohibition mentioned above. As explained in Halachah 3:11, generally, chametz can be destroyed by other means as well. However, this halachah deals with bread brought as sacrifices; hence, it is proper that they be burned (Rabbenu Manoach).

הלכה י
הָא לָמַדְתָּ שֶׁמֻּתָּר לֶאֱכל חָמֵץ בְּיוֹם אַרְבָּעָה עָשָׂר עַד סוֹף שָׁעָה רְבִיעִית. וְאֵין אוֹכְלִין בְּשָׁעָה חֲמִישִׁית אֲבָל נֶהֱנִין בּוֹ. וְהָאוֹכֵל בְּשָׁעָה שִׁשִּׁית מַכִּין אוֹתוֹ מַכַּת מַרְדּוּת. וְהָאוֹכֵל מִתְּחִלַּת שָׁעָה שְׁבִיעִית לוֹקֶה:
כסף משנה
10.
Thus, you have learned that it is permitted to eat chametz on the day of the fourteenth [of Nisan] until the end of the fourth hour.1as explained in the previous halachah. During the fifth hour, [chametz] is not eaten, but benefit may be derived from it.2Thus, during this time, a person may sell his chametz to gentiles or feed it to his animals. A person who eats chametz during the sixth hour is [punished by] "stripes for being rebellious."3The punishment given for transgressing a Rabbinic commandment. The Lechem Mishneh notes that the Rambam does not prescribe a punishment for a person who breaks the Rabbinic decree against eating chametz during the fifth hour.
The Tzafnat Paneach (Responsum 83) also differentiates between the fifth and sixth hours, calling the former, a Rabbinic safeguard, and the latter, a Rabbinic prohibition.
One who eats4With regard to the prohibition against benefiting from chametz, see commentary, Halachah 8. during the seventh hour is lashed.5as explained in Halachah 8.

זמנים הלכות חמץ ומצה פרק א
Zemanim Hametz and Matza Chapter 1