Halacha
הלכה א
הַמְקַדֵשׁ עַל תְּנַאי אִם נִתְקַיֵּם הַתְּנַאי מְקֻדֶּשֶׁת וְאִם לָאו אֵינָהּ מְקֻדֶּשֶׁת בֵּין שֶׁיִּהְיֶה הַתְּנַאי מִן הָאִישׁ בֵּין שֶׁיִּהְיֶה מִן הָאִשָּׁה. וְכָל תְּנַאי שֶׁבָּעוֹלָם בֵּין בְּקִדּוּשִׁין בֵּין בְּגֵּרוּשִׁין בֵּין בְּמִקָּח בֵּין בְּמִמְכָּר בֵּין בִּשְׁאָר דִּינֵי מָמוֹן צָרִיךְ לִהְיוֹת בִּתְנָאֵי אַרְבָּעָה דְּבָרִים:
כסף משנה
1.
[The following rules apply when a man] consecrates [a woman] based on a conditional agreement: If the condition is met, the kiddushin are binding. If not, they are of no consequence. This applies regardless of whether the condition was stipulated by the man or by the woman.Every [valid] conditional agreement whatsoever - whether with regard to kiddushin, divorce, commercial transactions or other questions of business law - must conform to the following four rules.1See Halachah 14 and notes.
הלכה ב
וְאֵלּוּ הֵן הַד' דְּבָרִים שֶׁל כָּל תְּנַאי. שֶׁיִּהְיֶה כָּפוּל. וְשֶׁיִּהְיֶה הֵן שֶׁלּוֹ קוֹדֵם לַלָּאו. וְשֶׁיִּהְיֶה הַתְּנַאי קוֹדֵם לַמַּעֲשֶׂה. וְשֶׁיִּהְיֶה הַתְּנַאי דָּבָר שֶׁאֶפְשָׁר לְקַיְּמוֹ. וְאִם חָסֵר הַתְּנַאי אֶחָד מֵהֶן הֲרֵי הַתְּנַאי בָּטֵל וּכְאִלּוּ אֵין שָׁם תְּנַאי כְּלָל אֶלָּא תִּהְיֶה זוֹ מְקֻדֶּשֶׁת אוֹ מְגֹרֶשֶׁת מִיָּד וְיִתְקַיֵּם הַמִּקָּח אוֹ הַמַּתָּנָה מִיָּד וּכְאִלּוּ לֹא הִתְנָה כְּלָל הוֹאִיל וְחָסֵר הַתְּנַאי אֶחָד מִן הָאַרְבָּעָה:
כסף משנה
2.
These are the four rules governing all conditional agreements:2We find a conditional agreement in the Torah: Moses' granting the lands of Transjordan to the tribes of Reuven and Gad (Numbers 32:29-30). All these four rules were evident in Moses' phrasing of the stipulation. Accordingly, our Sages (Kiddushin 61a) consider this a prototype for all future conditional agreements.a) the stipulation must be twofold [with both a positive and negative statement];
b) the positive aspect must be stated before the negative aspect;
c) the stipulation should be mentioned before the completion of the deed that one desires to make conditional;3This is the Rambam's interpretation of the requirement that in its Hebrew original states: שיהיה התנאי קודם למעשה. The Ra'avad (in his gloss on Halachah 4) interprets the phrase differently. He states that in the wording of the person making the stipulation, the stipulation must be stated before the result of its completion: e.g., "If you give me 200 zuz, you will be consecrated..., and if you do not give me that sum, you will not be consecrated." The Beit Shmuel 38:2 accepts the Ra'avad's interpretation and not that of the Rambam.
d) the stipulation must be something that is possible to comply with.
If one of these rules was not kept when a conditional agreement was made, the stipulation is nullified; it is as if there is no condition at all. Thus, [the woman] is either consecrated or divorced immediately, and the commercial agreement is completed as if no condition had ever been made, for one of the four rules of conditional agreements was not met.
הלכה ג
כֵּיצַד. הָאוֹמֵר לְאִשָּׁה אִם תִּתְּנִי לִי מָאתַיִם זוּז הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאִם לֹא תִּתְּנִי לִי לֹא תִּהְיִי מְקֻדֶּשֶׁת וְאַחַר שֶׁהִתְנָה תְּנַאי זֶה נָתַן לָהּ הַדִּינָר. הֲרֵי הַתְּנַאי קַיָּם וַהֲרֵי זוֹ מְקֻדֶּשֶׁת עַל תְּנַאי. וְאִם נָתְנָה לוֹ מָאתַיִם זוּז תִּהְיֶה מְקֻדֶּשֶׁת וְאִם לֹא נָתְנָה לוֹ אֵינָהּ מְקֻדֶּשֶׁת:
כסף משנה
3.
What is implied? [When a man] tells a woman: "If you give me 200 zuz, you are consecrated to me with this dinar. And if you do not give me [that sum], you are not consecrated," and after making this stipulation gives her the dinar, the condition is valid, and the kiddushin are subject to its terms. If she gives him 200 zuz, she is consecrated. If she does not give him, she is not consecrated.הלכה ד
אֲבָל אִם אָמַר לָהּ הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְנָתַן הַדִּינָר בְּיָדָהּ וְהִשְׁלִים הַתְּנַאי וְאָמַר אִם תִּתְּנִי לִי מָאתַיִם זוּז תִּהְיִי מְקֻדֶּשֶׁת וְאִם לֹא תִּתְּנִי לִי לֹא תִּהְיִי מְקֻדֶּשֶׁת הֲרֵי הַתְּנַאי בָּטֵל מִפְּנֵי שֶׁהִקְדִּים הַמַּעֲשֶׂה וְנָתַן בְּיָדָהּ וְאַחַר כָּךְ הִתְנָה. וְאַף עַל פִּי שֶׁהַכּל בְּתוֹךְ כְּדֵי דִּבּוּר הֲרֵי זוֹ מְקֻדֶּשֶׁת מִיָּד וְאֵינָהּ צְרִיכָה לִתֵּן לוֹ כְּלוּם:
כסף משנה
4.
If, however, [the man] told [the woman]: "Behold, you are consecrated to me with this dinar," gave her the dinar in her hand and then made a stipulation, saying: "If you give me 200 zuz you are consecrated," and if you do not give me [that sum] you are not consecrated," the stipulation is of no consequence, because he performed the deed first by giving it to her, and then making the stipulation.[The above applies] even if everything occurred within a brief span of time;4We have chosen a very loose translation. The Hebrew toch kedei dibbur has a precise connotation, meaning the amount of time it takes to say the words Shalom alecha rabbi umori. she is consecrated immediately and does not have to give [her husband] anything at all.
הלכה ה
וְכֵן אִם אָמַר לָהּ אִם תִּתְּנִי לִי מָאתַיִם זוּז הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאַחַר כָּךְ נָתַן הַדִּינָר בְּיָדָהּ הֲרֵי הַתְּנַאי בָּטֵל מִפְּנֵי שֶׁלֹּא כָּפַל תְּנָאוֹ. שֶׁהֲרֵי לֹא אָמַר לָהּ וְאִם לֹא תִּתְּנִי לֹא תִּהְיִי מְקֻדֶּשֶׁת וַהֲרֵי זוֹ מְקֻדֶּשֶׁת מִיָּד וְאֵינָהּ צְרִיכָה לִתֵּן לוֹ כְּלוּם:
כסף משנה
5.
Similarly, when [a man] tells [a woman]: "If you give me 200 zuz you are consecrated to me with this dinar," and then places the dinar in her hand, the stipulation is of no consequence, because the condition was not stated in a twofold manner. He did not tell her: "If you do not give me, you will not be consecrated." [Therefore] she is consecrated immediately without having to give him anything.הלכה ו
וְכֵן אִם אָמַר לָהּ אִם לֹא תִּתְּנִי לִי מָאתַיִם זוּז לֹא תִּהְיִי מְקֻדֶּשֶׁת לִי וְאִם תִּתְּנִי לִי מָאתַיִם זוּז הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאַחַר כָּךְ נָתַן הַדִּינָר בְּיָדָהּ הֲרֵי הַתְּנַאי בָּטֵל לְפִי שֶׁהִקְדִּים לָאו לְהֵן וַהֲרֵי זוֹ מְקֻדֶּשֶׁת מִיָּד וְאֵינָהּ צְרִיכָה לִתֵּן לוֹ כְּלוּם:
כסף משנה
6.
Similarly, when [a man] tells [a woman]: "If you do not give me 200 zuz, you will not be consecrated to me. But if you give me 200 zuz, you are consecrated to me with this dinar," and then places the dinar in her hand, the stipulation is of no consequence, because the negative dimension of the stipulation was stated before the positive one. [Therefore,] she is consecrated immediately without having to give him anything.הלכה ז
וְכֵן אִם אָמַר לָהּ אִם תַּעֲלִי לָרָקִיעַ אוֹ תֵּרְדִי לַתְּהוֹם הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאִם לֹא תַּעֲלִי לָרָקִיעַ וְלֹא תֵּרְדִי לַתְּהוֹם לֹא תִּהְיִי מְקֻדֶּשֶׁת וְאַחַר כָּךְ נָתַן הַדִּינָר בְּיָדָהּ הֲרֵי הַתְּנַאי בָּטֵל וַהֲרֵי הִיא מְקֻדֶּשֶׁת מִיָּד שֶׁהַדָּבָר יָדוּעַ שֶׁאִי אֶפְשָׁר לָהּ לְקַיֵּם תְּנַאי זֶה וְאֵין זֶה אֶלָּא כְּמַפְלִיגָהּ בִּדְבָרִים דֶּרֶךְ שְׂחוֹק וְהִתּוּל:
כסף משנה
7.
Similarly, when [a man] tells [a woman]: "If you ascend to the heavens or descend to the depths, you are consecrated to me with this dinar. But if you do not ascend to the heavens or descend to the depths, you are not consecrated." If he places the dinar in her hand afterwards, the stipulation is of no consequence, and the kiddushin are effective immediately. For it is well known that she cannot keep this stipulation; he is merely speaking facetiously in a jesting and teasing manner.הלכה ח
הֲרֵי שֶׁהִתְנָה בְּדָבָר שֶׁאֶפְשָׁר לַעֲשׂוֹתוֹ אֶלָּא שֶׁהַתּוֹרָה אָסְרָה אוֹתוֹ כְּגוֹן שֶׁאָמַר לְאִשָּׁה אִם תֹּאכְלִי חֵלֶב וְדָם הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאִם לֹא תֹּאכְלִי לֹא תִּהְיִי מְקֻדֶּשֶׁת. אִם תֹּאכְלִי בְּשַׂר חֲזִיר הֲרֵי זֶה גִּטֵּךְ וְאִם לֹא תֹּאכְלִי לֹא יְהֵא גֵּט. וְאַחַר שֶׁהִתְנָה נָתַן הַדִּינָר אוֹ הַגֵּט בְּיָדָהּ הֲרֵי הַתְּנַאי קַיָּם. וְאִם עָבְרָה וְאָכְלָה תִּהְיֶה מְקֻדֶּשֶׁת אוֹ מְגֹרֶשֶׁת. וְאִם לֹא אָכְלָה אֵינָהּ מְקֻדֶּשֶׁת וְאֵינָהּ מְגֹרֶשֶׁת. וְאֵין אוֹמְרִים בָּזֶה הֲרֵי הִתְנָה עַל מַה שֶּׁכָּתוּב בַּתּוֹרָה שֶׁהֲרֵי בְּיָדָהּ שֶׁלֹּא תֹּאכַל וְשֶׁלֹּא תִּתְקַדֵּשׁ וְלֹא תִּתְגָּרֵשׁ:
כסף משנה
8.
[The following rules apply when a man] makes a condition with regard to a deed that is possible to be performed, but that is forbidden by the Torah - e.g., he told a woman: "If you eat fat or blood, you are consecrated to me with this dinar. But if you do not eat fat or blood, you are not consecrated," or [a man tells his wife]: "If you eat the meat of pigs, this is your get. But if you do not eat it, the get is not effective." If, after making this stipulation, he placed the dinar or the get in her hand, the stipulation is valid. If the woman transgresses and eats [the forbidden article as stipulated], she will be either consecrated or divorced [accordingly]. It is not with regard to such a situation that it is said, "the person made a stipulation that contradicts what is written in the Torah." For the woman has the option not to eat and not to be consecrated or divorced.הלכה ט
וּבַמֶּה אָמְרוּ חֲכָמִים כָּל הַמַּתְנֶה עַל מַה שֶּׁכָּתוּב בַּתּוֹרָה תְּנָאוֹ בָּטֵל חוּץ מְדַבֵּר שֶׁבְּמָמוֹן שֶׁתְּנָאוֹ קַיָּם. כְּגוֹן שֶׁקִּדֵּשׁ אוֹ גֵּרֵשׁ אוֹ נָתַן אוֹ מָכַר עַל תְּנַאי שֶׁהוּא רוֹצֶה בִּתְנָאוֹ שֶׁיְּזַכֶּה עַצְמוֹ בְּדָבָר שֶׁלֹּא זִכְּתָה לוֹ תּוֹרָה וּמָנְעָה מִמֶּנּוּ אוֹ יִפְטֹר עַצְמוֹ בִּתְנָאוֹ מִדָּבָר שֶׁחִיְּבָה אוֹתוֹ בּוֹ הַתּוֹרָה שֶׁאוֹמְרִין לוֹ תְּנָאֲךָ בָּטֵל וּכְבָר נִתְקַיְּמוּ מַעֲשֶׂיךָ וְאֵין אַתָּה נִפְטָר מִדָּבָר שֶׁחִיְּבָה אוֹתְךָ בּוֹ הַתּוֹרָה וְלֹא תִּזְכֶּה בְּדָבָר שֶׁמָּנְעָה אוֹתְךָ מִמֶּנּוּ:
כסף משנה
9.
With regard [to which situations] did in fact our Sages say:5Kiddushin 19b. "Whenever a person makes a stipulation that contradicts what is written in the Torah, his stipulation is nullified, except with regard to financial matters, in which instances his stipulation is binding"?6An exception is made with regard to financial matters, because with regard to these matters the Torah grants the person the right to waive monetary privileges that are due him. Privileges that are not monetary in nature may not be waived.When a person consecrates, divorces, gives or sells, dependent on a stipulation through which he wants to acquire a right that the Torah did not grant him, but rather prevented him from obtaining, or to use this stipulation to free himself from an obligation for which the Torah made him liable. In such an instance, he is told, "Your stipulation is of no consequence. The deed you have performed is binding. You are not freed from any responsibility for which the Torah obligates you, nor can you acquire any privilege that the Torah does not grant you."
הלכה י
כֵּיצַד. כְּגוֹן שֶׁקִּדֵּשׁ אִשָּׁה עַל תְּנַאי שֶׁאֵין לָהּ עָלָיו שְׁאֵר כְּסוּת וְעוֹנָה. שֶׁאוֹמְרִין לוֹ בִּכְסוּת וּשְׁאֵר שֶׁהוּא תְּנַאי שֶׁבְּמָמוֹן תְּנָאֲךָ קַיָּם אֲבָל בְּעוֹנָה תְּנָאֲךָ בָּטֵל שֶׁהַתּוֹרָה חִיְּבָה אוֹתְךָ בְּעוֹנָה וַהֲרֵי זוֹ מְקֻדֶּשֶׁת וְאַתָּה חַיָּב בְּעוֹנָתָהּ וְאֵין בְּיָדְךָ לִפְטֹר עַצְמְךָ בִּתְנָאֲךָ. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה. וְכֵן הַמְקַדֵּשׁ יְפַת תֹּאַר עַל תְּנַאי שֶׁיִּתְעַמֵּר בָּהּ הֲרֵי זוֹ מְקֻדֶּשֶׁת וְאֵין לוֹ לְהִתְעַמֵּר בָּהּ שֶׁהֲרֵי הַתּוֹרָה מָנְעָה אוֹתוֹ מִלְּהִשְׁתַּעְבֵּד בָּהּ אַחַר שֶׁנִּבְעֲלָה. וְלֹא מִפְּנֵי תְּנָאוֹ יִזְכֶּה בְּדָבָר שֶׁמָּנְעָה אוֹתוֹ תּוֹרָה אֶלָּא תְּנָאוֹ בָּטֵל וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
10.
What is implied? For example, when a man consecrates a woman on condition that he is not obligated to provide her with her provisions or garments, nor grant her conjugal rights, he is told: "With regard to provisions and garments, your stipulation is binding, for these are financial obligations. With regard to conjugal rights, however, your condition is not binding,7Based on the Jerusalem Talmud (Bava Metzia, the conclusion of Chapter 7), the Ritba (Kiddushin 19a) and the Mordechai (gloss on Bava Metzia 93a) maintain that even conjugal rights can be considered to be a financial consideration, for it is a matter of physical pleasure. Nevertheless, this opinion is not accepted as halachah. Instead, withholding conjugal relations is considered a matter of physical anguish. Hence a woman does not have the prerogative of waiving this right. for the Torah has obligated you to grant these [to a woman]. Therefore, she is consecrated and you are obligated to grant her conjugal rights. You do not have the potential to free yourself of this responsibility with this stipulation." The same applies in all similar situations.Similarly, if a man consecrates a woman whom he took as a captive for sexual relations on condition that he may have her perform servile tasks,8Deuteronomy 21:11-14 describes the right of a soldier to have relations with a female captive of war whom he desires. Once he has relations with her, he may no longer treat her as a servant. she is consecrated and he is forbidden to have her perform these tasks, for after he had relations with her this was prohibited by the Torah. His stipulation does not empower him to a privilege that the Torah held back from him. The same applies in all similar situations.
הלכה יא
הִתְנָה עַל הָאִשָּׁה בִּשְׁעַת קִדּוּשִׁין אוֹ בִּשְׁעַת גֵּרוּשִׁין שֶׁתִּבָּעֵל לְאָבִיהָ וּלְאָחִיהָ אוֹ לִבְנָהּ וְכַיּוֹצֵא בָּזֶה הֲרֵי זֶה כְּמִי שֶׁהִתְנָה עָלֶיהָ שֶׁתַּעֲלֶה לָרָקִיעַ אוֹ שֶׁתֵּרֵד לַתְּהוֹם וּתְנָאוֹ בָּטֵל שֶׁאֵין בְּיָדָהּ שֶׁיַּעַבְרוּ אֲחֵרִים וְיָבֹאוּ עַל הָעֶרְוָה וְנִמְצָא שֶׁהִתְנָה עִמָּהּ בְּדָבָר שֶׁאֵינוֹ בְּיָדָהּ לְקַיְּמוֹ. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
11.
If a man established a condition with a woman at the time of kiddushin or divorce requiring her to engage in sexual relations with her father, her brother, her son or the like, it is as if he made a stipulation that she ascend to the heavens or descend to the depths, and his condition is of no consequence. For it is not within the woman's capacity to cause others to transgress and to engage in a forbidden sexual relationship. Thus, he has made a stipulation that she is incapable of fulfilling. The same applies with regard to all similar instances.הלכה יב
אֲבָל אִם הִתְנָה עָלֶיהָ שֶׁיִּתֵּן לִי פְּלוֹנִי חֲצֵרוֹ אוֹ שֶׁיַּשִּׂיא בִּתּוֹ לִבְנִי וְכַיּוֹצֵא בָּזֶה תְּנָאוֹ קַיָּם שֶׁהֲרֵי אֶפְשָׁר בְּיָדָהּ לְקַיְּמוֹ וְתִתֵּן לִפְלוֹנִי מָמוֹן רַב עַד שֶׁיִּתֵּן לוֹ חֲצֵרוֹ וְעַד שֶׁיַּשִּׂיא בִּתּוֹ לִבְנוֹ שֶׁהֲרֵי אֵין כָּאן עֲבֵרָה. וְכֵן כָּל כַּיּוֹצֵא בָּזֶה:
כסף משנה
12.
If, however, the man made a stipulation that she [influence] so and so to "give me his courtyard or to have his daughter marry my son," the stipulation is binding. For it is in her capacity to fulfill it, she can give so and so a large amount of money so that he will [consent to] give the man [making the condition] his courtyard or have his daughter marry that man's son. For in this instance, there is no sin involved. The same applies with regard to all similar instances.הלכה יג
שִׂים כָּל אֵלּוּ הַדְּבָרִים שֶׁל תְּנָאִים לְנֶגֶד עֵינֶיךָ תָּמִיד. וְכָל מָקוֹם שֶׁאַתָּה שׁוֹמֵעַ הַמְקַדֵּשׁ עַל תְּנַאי כָּךְ וְכָךְ אוֹ הַנּוֹתֵן גֵּט עַל תְּנַאי כָּךְ וְכָךְ אוֹ הַמּוֹכֵר אוֹ הַנּוֹתֵן עַל תְּנַאי תֵּדַע שֶׁהַתְּנַאי יֵשׁ בּוֹ אַרְבָּעָה דְּבָרִים אֵלּוּ שֶׁבֵּאַרְנוּ כְּדֵי שֶׁלֹּא נִהְיֶה צְרִיכִין לְפָרֵשׁ אוֹתָן בְּכָל מָקוֹם. וְאִם חָסֵר אֶחָד מֵהֶן אֵין כָּאן תְּנַאי:
כסף משנה
13.
Have in mind at all times all these guidelines that have been mentioned with regard to conditional agreements. Whenever you hear the expression "A man consecrated [a woman] on the basis of these and these conditions," "gave a divorce on the basis of these and these conditions," or made a sale or gave a present conditionally, you will know that the condition must fit the four rules mentioned. Thus, it will not be necessary to repeat them on every occasion. If one of these rules is not kept, the stipulation is of no consequence.הלכה יד
יֵשׁ מִקְצָת גְּאוֹנִים אַחֲרוֹנִים שֶׁאָמְרוּ שֶׁאֵין צָרִיךְ אָדָם לִכְפּל תְּנָאוֹ אֶלָּא בְּגִטִּין וְקִדּוּשִׁין בִּלְבַד אֲבָל בְּדִינֵי מָמוֹן אֵינוֹ צָרִיךְ לִכְפּל. וְאֵין רָאוּי לִסְמֹךְ עַל דָּבָר זֶה שֶׁכְּפִילַת הַתְּנַאי עִם שְׁאָר הָאַרְבָּעָה דְּבָרִים מִתְּנַאי בְּנֵי גָּד וּבְנֵי רְאוּבֵן לָמְדוּ אוֹתָן חֲכָמִים (במדבר לב כט) "אִם יַעַבְרוּ בְּנֵי גָּד" וְגוֹ' (במדבר לב ל) "וְאִם לֹא יַעַבְרוּ" וּתְנַאי זֶה לֹא הָיָה לֹא בְּגִטִּין וְלֹא בְּקִדּוּשִׁין. וְכָזֶה הוֹרוּ גְּדוֹלֵי הַגְּאוֹנִים הָרִאשׁוֹנִים וְכֵן רָאוּי לַעֲשׂוֹת:
כסף משנה
14.
Some of the later geonim9The commentaries have pointed to Rabbenu Yitzchak Alfasi and Rabbenu Shmuel ben Chofni HaCohen. maintain that a person is required to make a conditional statement twofold only with regard to kiddushin and divorce. With regard to financial matters, by contrast, a twofold statement need not be made.It is not proper to rely on this ruling, for our Sages derived the need to make a twofold statement of the condition, and the other four rules, from the condition made [with] the members [of the tribes] of Gad and Reuven, as [Numbers 38:29-30] states: "If the members [of the tribes] of Gad... cross over. But if they do not cross over...." And this condition involved neither kiddushin nor divorce. [My ruling echoes] the decisions of the great geonim of the previous eras, and it is fitting to follow it.10The Ra'avad, the Ramban and the Rashba differ with the Rambam's reasoning. According to the position of these authorities, it is only one Sage, Rabbi Meir, who maintains that the rules regarding conditional agreements were derived from the agreement made between Moses and the tribes of Reuven and Gad. They maintain that the need to repeat the condition applies only with regard to kiddushin, and was instituted only because of the severity of the establishment and annulment of the marriage relationship. With regard to other matters, however, there is no such requirement. The Tur and the Shulchan Aruch (Choshen Mishpat 241:9) follow the Rambam's view.
הלכה טו
הַמְקַדֵּשׁ עַל תְּנַאי כְּשֶׁיִּתְקַיֵּם הַתְּנַאי תִּהְיֶה מְקֻדֶּשֶׁת מִשָּׁעָה שֶׁנִּתְקַיֵּם הַתְּנַאי לֹא מִשָּׁעָה שֶׁנִּתְקַדְּשָׁה. כֵּיצַד. הָאוֹמֵר לְאִשָּׁה אִם אֶתֵּן לִיךְ מָאתַיִם זוּז בְּשָׁנָה זוֹ הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי בְּדִינָר זֶה וְאִם לֹא אֶתֵּן לִיךְ לֹא תִּהְיִי מְקֻדֶּשֶׁת וְנָתַן הַדִּינָר לְיָדָהּ בְּנִיסָן וְנָתַן לָהּ הַמָּאתַיִם זוּז שֶׁהִתְנָה עִמָּהּ בֶּאֱלוּל הֲרֵי זוֹ מְקֻדֶּשֶׁת מֵאֱלוּל. לְפִיכָךְ אִם קִדְּשָׁהּ אַחֵר קֹדֶם שֶׁיִּתְקַיֵּם הַתְּנַאי שֶׁל רִאשׁוֹן הֲרֵי זוֹ מְקֻדֶּשֶׁת לַשֵּׁנִי. וְכֵן הַדִּין בְּגִטִּין וּבְמָמוֹנוֹת בְּשָׁעָה שֶׁיִּתְקַיֵּם הַתְּנַאי הוּא שֶׁיִּהְיֶה גֵּט אוֹ יִתְקַיֵּם הַמִּקָּח אוֹ הַמַּתָּנָה:
כסף משנה
15.
When a man consecrates a woman conditionally, the kiddushin become effective at the time the stipulation is fulfilled, and not at the time of the [original] kiddushin.What is implied? [For example, a man] tells a woman: "If I give you 200 zuz this year, you are consecrated to me with this dinar. But if I do not give you, you are not consecrated." If he [made these statements and] gave her the dinar in Nisan, but gave her the 200 zuz that he stipulated only in Elul, it is in Elul that the consecration takes effect. Therefore, if another person consecrates her before the first completes carrying out his stipulation, she is consecrated to the second.
Similar laws apply with regard to divorce and monetary law. When the stipulation is fulfilled, the divorce is effective or the sale or gift is completed.11The above applies when the agreement is made verbally. If, however, a conditional sale or a present is recorded in a legal document, it is considered to be effective retroactively from the date stated in the document, although the stipulation is not carried out until much later.
Others maintain that the same principle applies with regard to a get, and if a date is included in a conditional bill of divorce, the divorce is retroactively effective from the date of the get, even though the stipulation is carried out much later. As stated in Hilchot Gerushin 8:1, the Rambam does not follow this approach. (See Shulchan Aruch, Even HaEzer 143:2.)
הלכה טז
בַּמֶּה דְּבָרִים אֲמוּרִים בְּשֶׁהָיָה שָׁם תְּנַאי וְלֹא אָמַר מֵעַכְשָׁו. אֲבָל אִם אָמַר לָהּ הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי מֵעַכְשָׁו בְּדִינָר זֶה אִם אֶתֵּן לִיךְ מָאתַיִם זוּז וּלְאַחַר זְמַן נָתַן לָהּ מָאתַיִם זוּז הֲרֵי זוֹ מְקֻדֶּשֶׁת לְמַפְרֵעַ מִשְּׁעַת הַקִּדּוּשִׁין אַף עַל פִּי שֶׁלֹּא נַעֲשָׂה תְּנָאוֹ אֶלָּא לְאַחַר זְמַן מְרֻבֶּה. לְפִיכָךְ אִם קִדְּשָׁהּ הַשֵּׁנִי קֹדֶם שֶׁיַּעֲשֶׂה הַתְּנַאי אֵינָהּ מְקֻדֶּשֶׁת. וְכֵן הַדִּין בְּגִטִּין וּבְמָמוֹן:
כסף משנה
16.
When does the above apply? When a stipulation was made, and [the person making it did not state that the agreement took effect] from this time onward. If, however, [a man] told [a woman]: "Behold, you are consecrated to me from this time onward with this dinar if I give you 200 zuz,"12In such an instance, the stipulation need not be restated, as mentioned in the following halachah. when at a later date he gives her the 200 zuz she is consecrated. Retroactively, the kiddushin are considered to have taken effect at the time they were given, despite the fact that the stipulation was not fulfilled until after much time had passed. Therefore, if a second person consecrates her before the stipulation has been fulfilled, she is not consecrated to that [second] person. Similar laws apply with regard to divorce and monetary law.הלכה יז
כָּל הָאוֹמֵר מֵעַכְשָׁו לֹא יִצְטָרֵךְ לִכְפּל תְּנָאוֹ וְלֹא לְהַקְדִּים הַתְּנַאי עַל הַמַּעֲשֶׂה אֶלָּא אַף עַל פִּי שֶׁהִקְדִּים הַמַּעֲשֶׂה תְּנָאוֹ קַיָּם. אֲבָל צָרִיךְ לְהַתְנוֹת בְּדָבָר שֶׁאֶפְשָׁר לְקַיְּמוֹ. וְאִם הִתְנָה בְּדָבָר שֶׁאִי אֶפְשָׁר לְקַיְּמוֹ הֲרֵי זֶה כְּמַפְלִיג בִּדְבָרִים וְאֵין שָׁם תְּנַאי. וְכָל הָאוֹמֵר עַל מְנָת כְּאוֹמֵר מֵעַכְשָׁו וְאֵינוֹ צָרִיךְ לִכְפּל הַתְּנַאי וְלֹא לְהַקְדִּימוֹ לַמַּעֲשֶׂה:
כסף משנה
17.
Whenever a person makes a stipulation and states [that it is effective] "from this time onward," it is not necessary for him to make a twofold statement of the stipulation,13Since the condition does not have to be restated, there is also no need for the positive statement to precede the negative. nor is it necessary to state the stipulation before performing the deed involved.14This follows the Rambam's interpretation of the Talmud's wording שיהיה התנאי קודם למעשה, as explained in Halachah 2. Even when he performs the deed first, his stipulation is effective. He must, however, make a stipulation that is possible to fulfill. A person who makes a stipulation that is impossible to fulfill is merely speaking facetiously; there is no [intent to make] a [binding] stipulation.When a person appends a stipulation to an agreement using the wording al menat ("on condition that"), the rules that apply when the person states "from this time onward" also apply.15Tosafot and many subsequent Ashkenazic authorities do not accept this ruling. The difference of opinion is noted by the Shulchan Aruch (Even HaEzer 144:4). It is not necessary for him to make a twofold statement of the stipulation, nor is it necessary to state the stipulation before performing the deed involved.
הלכה יח
כֵּיצַד. הָאוֹמֵר לְאִשָּׁה הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי עַל מְנָת שֶׁתִּתְּנִי לִי מָאתַיִם זוּז. הֲרֵי זֶה גִּטֵּךְ עַל מְנָת שֶׁתִּתְּנִי לִי מָאתַיִם זוּז. הֲרֵי חָצֵר זוֹ נְתוּנָה לִיךְ בְּמַתָּנָה עַל מְנָת שֶׁתִּתְּנִי לִי מָאתַיִם זוּז. הֲרֵי תְּנָאוֹ קַיָּם וְנִתְקַדְּשָׁה אוֹ נִתְגָּרְשָׁה וְזָכְתָה זוֹ בֶּחָצֵר וְהֵם יִתְּנוּ הַמָּאתַיִם זוּז. וְאִם לֹא נָתְנוּ לֹא תִּהְיֶה זוֹ מְקֻדֶּשֶׁת וְלֹא מְגֹרֶשֶׁת וְלֹא תִּזְכֶּה זוֹ בֶּחָצֵר. וְאַף עַל פִּי שֶׁלֹּא כָּפַל תְּנָאוֹ וְאַף עַל פִּי שֶׁהִקְדִּים הַמַּעֲשֶׂה לַתְּנַאי וְנָתַן הַקִּדּוּשִׁין אוֹ הַגֵּט בְּיָדָהּ וְהֶחֱזִיקָה זוֹ בֶּחָצֵר וְאַחַר כָּךְ הִשְׁלִים תְּנָאוֹ. שֶׁהֲרֵי כְּשֶׁיִּתְקַיֵּם הַתְּנַאי תִּזְכֶּה זוֹ בֶּחָצֵר וְתִתְקַדֵּשׁ זוֹ וְתִתְגָּרֵשׁ מִשָּׁעָה רִאשׁוֹנָה שֶׁבָּהּ נַעֲשָׂה הַמַּעֲשֶׂה כְּאִלּוּ לֹא הָיָה שָׁם תְּנַאי כְּלָל:
כסף משנה
18.
What is implied? When [a man] tells a woman: "Behold, you are consecrated to me on condition that you give me 200 zuz," "here is your get on condition that you give me 200 zuz," or "this courtyard is given to you as a present on condition that you give me 200 zuz," the stipulation is binding. She is consecrated or divorced, or she acquires the field, but she must give the 200 zuz. If she does not give [the money], she will not be consecrated or divorced, nor will she acquire the field.[The above applies] even when the man did not make a twofold condition, and even though he performed the deed before stating the condition - i.e., he placed the kiddushin or the get in her hand or let her take possession of the courtyard, and then completed [the statement of] his stipulation. [The rationale for these leniencies is that] when the stipulation is fulfilled, she retroactively either acquires the field or is consecrated or divorced from the time the deed was performed, as if a stipulation had never been made at all.16Among the other rationales offered are that the rules for a conditional agreement are derived from the agreement between Moses and the tribes of Gad and Reuven, and in that instance that condition was phrased using the term "if," rather than "from this time onward" or "on condition that" (Rabbenu Yitzchak Alfasi). The Ra'avad explains that stating a stipulation using the wording "if" nullifies the act the person performs. For a stipulation to have this power, it must be worded precisely. If, however, the wording "on condition that" or "from now onward" is used, the implication is that the act is not nullified, but is merely dependent on the fulfillment of the condition. Since the stipulation is not that powerful, its wording need not be as precise.