Halacha

הלכה א
כְּבָר בֵּאַרְנוּ שֶׁקִּיּוּם שְׁטָרוֹת מִדִּבְרֵיהֶם כְּדֵי שֶׁלֹּא תִּנְעל דֶּלֶת בִּפְנֵי לוֹוִין. אַף עַל פִּי כֵן אֵין מְקַיְּמִין שְׁטָרוֹת אֶלָּא בִּשְׁלֹשָׁה אֲפִלּוּ שְׁלָשְׁתָּן הֶדְיוֹטוֹת מִפְּנֵי שֶׁהוּא דִּין. וּלְפִיכָךְ אֵין מְקַיְּמִין שְׁטָרוֹת בַּלַּיְלָה כְּמוֹ שֶׁבֵּאַרְנוּ:
כסף משנה
1.
As explained, the verification of the authenticity of the signatures of the witnesses to legal documents is a Rabbinic provision so that loans will be given freely. Nevertheless, we do not verify the authenticity of a legal document except in a court of three judges, for it is a judgment. Ordinary people, however, are acceptable to serve as the judges. For this reason, the authenticity of legal documents may not be verified at night, as we explained.

הלכה ב
בְּאֶחָד מֵחֲמִשָּׁה דְּרָכִים מִתְקַיֵּם הַשְּׁטָר בְּבֵית דִּין. הַדֶּרֶךְ הָאֶחָד שֶׁיִּהְיוּ דַּיָּנִים מַכִּירִין כְּתַב יְדֵי הָעֵדִים שֶׁזּוֹ עֵדוּת פְּלוֹנִי וְזוֹ עֵדוּת פְּלוֹנִי. הַדֶּרֶךְ הַשֵּׁנִי שֶׁיַּחְתְּמוּ הָעֵדִים בִּפְנֵיהֶם. הַדֶּרֶךְ הַשְּׁלִישִׁי שֶׁיָּבוֹאוּ הָעֵדִים הַחֲתוּמִים בִּפְנֵיהֶם וְיֹאמַר כָּל אֶחָד וְאֶחָד זֶה כְּתַב יָדִי וַאֲנִי עֵד בַּדָּבָר הַזֶּה. הַדֶּרֶךְ הָרְבִיעִי שֶׁאִם מֵתוּ עֵדֵי הַשְּׁטָר אוֹ שֶׁהָיוּ בִּמְדִינָה אַחֶרֶת יָבוֹאוּ עֵדִים וְיָעִידוּ עַל כְּתַב יָדָן שֶׁהוּא זֶה. הַדֶּרֶךְ הַחֲמִישִׁי שֶׁיִּהְיֶה כְּתַב יָדָן יוֹצֵא מִשְּׁטָרוֹת אֲחֵרִים וְעוֹרְכִין בֵּית דִּין זֶה הַכְּתָב לְאוֹתוֹ הַכְּתָב שֶׁבִּשְׁטָרוֹת אֲחֵרִים וְיִהְיֶה דּוֹמֶה זֶה לָזֶה וְיֵרָאֶה לָהֶם בְּיַחַד שֶׁכְּתַב יְדֵי אֵלּוּ הוּא כְּתַב יְדֵי אֵלּוּ:
כסף משנה
2.
The authenticity of the signatures of the witnesses to legal documents may be verified in any of five ways:
a) the judges recognize the handwriting of the witnesses and know that this is so-and-so's signature and that this is so-and-so's signature;
b) the witnesses sign the legal document in their presence;
c) the witnesses who signed come and each testifies in the presence of the judges saying, "This is my signature and I am a witness to this matter";
d) if the witnesses to the legal document died or they were in another locale, other witnesses may come and testify to the authenticity of their signatures;
e) if the witnesses' signatures were found on other legal documents, the court compares these signatures to the signatures on those documents, seeing that they resemble each other and the signatures on these documents match these signatures.

הלכה ג
אֵין מְקַיְּמִין אֶת הַשְּׁטָר מִשְּׁטָרוֹת אֲחֵרִים אֶלָּא מִשְּׁנֵי שְׁטָרוֹת שֶׁל שְׁתֵּי שָׂדוֹת שֶׁאֲכָלוּם בַּעֲלֵיהֶן שָׁלֹשׁ שָׁנִים אֲכִילָה גְּלוּיָה נְכוֹנָה בְּלֹא שׁוּם יִרְאָה וְלֹא פַּחַד מִתְּבִיעָה בָּעוֹלָם כְּדֶרֶךְ שֶׁאוֹכְלִין כָּל בַּעֲלֵי שָׂדוֹת שְׂדוֹתֵיהֶן. אוֹ מִשְּׁנֵי שִׁטְרֵי כְּתֻבּוֹת. וְהוּא שֶׁיֵּצְאוּ שְׁנֵי הַשְּׁטָרוֹת מִתַּחַת יְדֵי אַחֵר לֹא מִתַּחַת יְדֵי זֶה שֶׁרוֹצֶה לְקַיֵּם שְׁטָרוֹ שֶׁמָּא הוּא זִיֵּף הַכּל. וְכֵן מְקַיְּמִין הַשְּׁטָר מִשְּׁטָר שֶׁקָּרָא עָלָיו עַרְעָר וְהֻחְזַק בְּבֵית דִּין מְקַיְּמִין מִמֶּנּוּ לְבַדּוֹ כְּמוֹ שֶׁמְּקַיְּמִין מִשְּׁטַר שְׁתֵּי שָׂדוֹת אוֹ מִשְּׁתֵי כְּתֻבּוֹת:
כסף משנה
3.
The authenticity of the signatures of the witnesses to legal documents should not be verified from documents other than:
a) two deeds of sale from two fields whose owners benefited from them for three years in a proper and conspicuous manner without fear or dread from any claim in the world as all the owners of fields benefit from their properties; or b) two ketubot.
These two legal documents must be in the possession of another person and not in the possession of the person who seeks to validate his legal document, for it is possible he forged all the signatures. Similarly, we may validate a legal document by comparing the signatures of the witnesses to those on a legal document whose authenticity was challenged and then verified by a court of law. Such a legal document alone can be used to verify the authenticity of the signatures to a legal document just as a legal document can be validated by comparing it to the deeds of sale for two fields or two ketubot.

הלכה ד
בֵּית דִּין שֶׁכָּתְבוּ בְּמוֹשַׁב שְׁלֹשָׁה הָיִינוּ וְנִתְקַיֵּם שְׁטָר זֶה בְּפָנֵינוּ הֲרֵי זֶה מְקֻיָּם אַף עַל פִּי שֶׁלֹּא פֵּרְשׁוּ בְּאֵי זֶה דֶּרֶךְ מֵחֲמִשָּׁה דְּרָכִים נִתְקַיֵּם. שֶׁאֵין חוֹשְׁשִׁין לְבֵית דִּין שֶׁמָּא יִטְעוּ. וּכְבָר נָהֲגוּ כָּל בָּתֵּי דִּינִין שֶׁרָאִינוּ וְשָׁמַעְנוּ שֶׁיִּכְתְּבוּ הַדֶּרֶךְ שֶׁנִּתְקַיֵּם בָּהּ לִפְנֵיהֶם:
כסף משנה
4.
When a court writes on a legal document: "In a sitting of three judges, the authenticity of this legal document was validated in our presence," it is validated even though they did not state in which of the five ways it was validated. For we do not suspect that the court erred. Nevertheless, it has already become accepted practice for all the courts which we have seen and about whom we have heard for the judges to describe the manner in which the document was validated.

הלכה ה
וּלְעוֹלָם אֵין בֵּית דִּין בּוֹדְקִין אַחַר בֵּית דִּין אַחֵר אֶלָּא מַחֲזִיקִין אוֹתָן שֶׁהֵן בְּקִיאִין וְלֹא יִטְעוּ. אֲבָל בּוֹדְקִין אַחַר הָעֵדִים:
כסף משנה
5.
A court never checks whether another court validated a legal document in a correct manner. Instead, we act under the presumption that they were knowledgeable and did not err. We do, however, check the witnesses.

הלכה ו
שְׁלֹשָׁה שֶׁיָּשְׁבוּ לְקַיֵּם אֶת הַשְּׁטָר וּמֵת אֶחָד מֵהֶם צְרִיכִין לִכְתֹּב בְּמוֹשַׁב שְׁלֹשָׁה הָיִינוּ וְהָאֶחָד אֵינֶנּוּ. שֶׁמָּא יֹאמַר הָרוֹאֶה בֵּית דִּין בִּשְׁנַיִם קִיְּמוּהוּ. אֲפִלּוּ הָיָה כָּתוּב בּוֹ בְּבֵית דִּין יֹאמַר שֶׁמָּא דִּמּוּ שֶׁשְּׁנַיִם בֵּית דִּין הֵם. וְאִם יֵשׁ בּוֹ מַשְׁמָע שֶׁהָיוּ שְׁלֹשָׁה אֵינוֹ צָרִיךְ:
כסף משנה
6.
When three judges sit to validate the authenticity of a legal document and one of them dies, the remaining judges should write: "We sat in a session of three judges, one of the judges exists no longer," lest an observer say: "A court of two judges validated it." Even if the validation states that it was performed by a court, it would be insufficient, lest an observer say: "Perhaps they thought that two judges could constitute a court." If their wording implied that there were three judges, there is no need to mention the death of the other judge.

הלכה ז
שְׁלֹשָׁה שֶׁיָּשְׁבוּ לְקַיֵּם אֶת הַשְּׁטָר וּבָאוּ שְׁנֵי עֵדִים וְעִרְעֲרוּ עַל אֶחָד מֵהֶן שֶׁהוּא גַּזְלָן וְכַיּוֹצֵא בּוֹ וּבָאוּ שְׁנַיִם אֲחֵרִים וְהֵעִידוּ שֶׁחָזַר בִּתְשׁוּבָה. אִם עַד שֶׁלֹּא חָתְמוּ הֵעִידוּ שֶׁחָזַר הֲרֵי זֶה חוֹתֵם עִמָּהֶם שֶׁהֲרֵי שְׁלֹשָׁה הָיוּ וְאִם אַחַר שֶׁחָתְמוּ הַשְּׁנַיִם הֵעִידוּ עָלָיו שֶׁחָזַר בִּתְשׁוּבָה אֵינוֹ חוֹתֵם עִמָּהֶן שֶׁהֲרֵי הוּא כְּמִי שֶׁאֵינוֹ בְּעֵת חֲתִימַת הַשְּׁנַיִם. בַּמֶּה דְּבָרִים אֲמוּרִים כְּשֶׁעִרְעֲרוּ עָלָיו בַּעֲבֵרָה. אֲבָל עִרְעֲרוּ עָלָיו בִּפְגַם מִשְׁפָּחָה כְּמוֹ שֶׁאָמְרוּ אִמּוֹ לֹא נִשְׁתַּחְרְרָה וְעֶבֶד הוּא אוֹ לֹא נִתְגַּיְּרָה וְעַכּוּ''ם הוּא וְנוֹדַע אַחַר שֶׁחָתְמוּ הַשְּׁנַיִם שֶׁאֵין בְּמִשְׁפַּחְתּוֹ פְּגָם וְשֶׁהוּא כָּשֵׁר הֲרֵי זֶה חוֹתֵם עִמָּהֶם שֶׁזֶּה גִּלּוּי דָּבָר שֶׁהָיָה מִקֹּדֶם הוּא:
כסף משנה
7.
The following principles apply when there is a question if one of the judges was acceptable to serve in his position. For example, three judges sat to validate the authenticity of a legal document. Two witnesses came and challenged the propriety of one of the judges, saying that he was a robber or the like. Two others came and testified that he repented. If, before the judges signed, they testified that he repented, he may sign with them. For there were three acceptable judges at the time of the signing. If it was not until after the other two judges signed that the witnesses testified that he repented, the third judge may not sign together with them. For it is as if he did not exist at the time the other two signed.
When does the above apply? When his propriety was challenged because of a transgression. Different rules apply, however, when, however, his propriety was challenged because of a blemish in his lineage, e.g., they said: "His mother was never freed, and he is a servant," or "His mother never converted and he is a gentile." If after the other two judges signed, it was discovered that he does not have this type of blemished lineage and he is fit to serve as a judge, he may sign together with the other two. The rationale is that this is merely the revelation of a fact that existed previously.

הלכה ח
מֻתָּר לִכְתֹּב הַקִּיּוּם בַּשְּׁטָר קֹדֶם שֶׁיִּתְקַיֵּם הַשְּׁטָר שֶׁאֵין הַכְּתִיבָה עִקָּר אֶלָּא הַחֲתִימָה. וְאֵין הַדַּיָּנִים צְרִיכִין לִקְרוֹת הַשְּׁטָר שֶׁמְּקַיְּמִין אוֹתוֹ אֶלָּא מְקַיְּמִין אוֹתוֹ מֵעֵדָיו אַף עַל פִּי שֶׁלֹּא יָדְעוּ מַה כָּתוּב בּוֹ:
כסף משנה
8.
It is permitted to write the validation on the document before the signatures on the document are validated. For it is the judges' signing of the validation, not the writing of it that is of fundamental importance.
The judges do not have to read the legal document when they validate its authenticity. Instead, they validate it based on the signatures of the witnesses even if they do not know what was written in it.

שופטים הלכות עדות פרק ו
Shoftim Edus Chapter 6