Kiddushin 3:4 - 3:5

Rabbi Meir says: Any condition that is not doubled, i.e., which does not specify both the result of fulfilling the condition and the result of the condition remaining unfulfilled, like the condition Moses stipulated with the children of Gad and the children of Reuben who sought to settle on the eastern side of the Jordan, is not a valid condition and is not taken into account at all. As it is stated: “And Moses said to them, if the children of Gad and the children of Reuben pass over the Jordan with you, every man armed for battle before the Lord, and the land shall be subdued before you, then you shall give them the land of Gilead for a possession” (Numbers 32:29). And it is written afterward: “But if they will not pass over armed with you, they shall receive a possession among you in the land of Canaan” (Numbers 32:30). Rabbi Ḥanina ben Gamliel says: One cannot derive the requirements of conditions in general from that particular case, as with regard to the nullification of the condition of the children of Gad and Reuben it was necessary to state the matter, as otherwise, if the verse had not specified both sides of the condition, it might have been thought it meant that they will not inherit even in the land of Canaan. One might have thought that if the tribes of Gad and Reuben would not fulfill the condition, they would forfeit their right to inherit anywhere. It was therefore necessary to specify that they would not lose their portion in Eretz Yisrael. Consequently, it is possible that with regard to a standard condition, where no such misunderstanding is likely to take place, it is not necessary to mention both sides.

רַבִּי מֵאִיר אוֹמֵר, כָּל תְּנַאי שֶׁאֵינוֹ כִתְנַאי בְּנֵי גָד וּבְנֵי רְאוּבֵן, אֵינוֹ תְנַאי, שֶׁנֶּאֱמַר (במדבר לב), וַיֹּאמֶר משֶׁה אֲלֵהֶם אִם יַעַבְרוּ בְנֵי גָד וּבְנֵי רְאוּבֵן, וּכְתִיב, וְאִם לֹא יַעַבְרוּ חֲלוּצִים. רַבִּי חֲנִינָא בֶן גַּמְלִיאֵל אוֹמֵר, צָרִיךְ הָיָה הַדָּבָר לְאָמְרוֹ, שֶׁאִלְמָלֵא כֵן, יֵשׁ בְּמַשְׁמַע שֶׁאֲפִלּוּ בְאֶרֶץ כְּנַעַן לֹא יִנְחָלוּ:

With regard to one who betroths a woman and later says: When I betrothed her I thought that she was the daughter of a priest, and it turned out that she is the daughter of a Levite, or if he claims that he thought she was the daughter of a Levite and she is actually the daughter of a priest, or if he claims that he thought she was poor and she is wealthy; or wealthy and she is poor, in all of these cases she is betrothed, because she did not mislead him, and no explicit condition was stated with regard to these matters. With regard to one who says to a woman: You are hereby betrothed to me after I convert, or: After you convert, or if he was a Canaanite slave and says: After I am emancipated, or if she was a Canaanite maidservant and he says: After you are emancipated, or if he says to a married woman: After your husband dies, or to his wife’s sister: After your sister dies, or if he says to a woman awaiting levirate marriage or ḥalitza from a brother-in-law [yavam], who in the opinion of this tanna cannot be betrothed by another man: After your yavam performs ḥalitza for you, in all these cases she is not betrothed. Since he cannot betroth her at the present time, his attempt at betrothal is ineffective. And similarly, with regard to one who says to another: If your wife gives birth to a female the child is hereby betrothed to me, even if she becomes pregnant, or is pregnant but her pregnancy is not known, if she gives birth to a girl, that child is not betrothed to him. But if he said this when the wife of the other man was pregnant and her fetus was discernible at the time, i.e., her pregnancy was known, his statement is upheld, and therefore if she gives birth to a girl, the child is betrothed to him.

הַמְקַדֵּשׁ אֶת הָאִשָּׁה וְאָמַר, כְּסָבוּר הָיִיתִי שֶׁהִיא כֹהֶנֶת וַהֲרֵי הִיא לְוִיָּה, לְוִיָּה וַהֲרֵי הִיא כֹהֶנֶת, עֲנִיָּה וַהֲרֵי הִיא עֲשִׁירָה, עֲשִׁירָה וַהֲרֵי הִיא עֲנִיָּה, הֲרֵי זוֹ מְקֻדֶּשֶׁת, מִפְּנֵי שֶׁלֹּא הִטְעַתּוּ. הָאוֹמֵר לְאִשָּׁה, הֲרֵי אַתְּ מְקֻדֶּשֶׁת לִי לְאַחַר שֶׁאֶתְגַּיֵּר אוֹ לְאַחַר שֶׁתִּתְגַּיְּרִי, לְאַחַר שֶׁאֶשְׁתַּחְרֵר אוֹ לְאַחַר שֶׁתִּשְׁתַּחְרְרִי, לְאַחַר שֶׁיָּמוּת בַּעֲלֵךְ אוֹ לְאַחַר שֶׁתָּמוּת אֲחוֹתֵךְ, לְאַחַר שֶׁיַּחֲלֹץ לָךְ יְבָמֵךְ, אֵינָהּ מְקֻדֶּשֶׁת. וְכֵן הָאוֹמֵר לַחֲבֵרוֹ, אִם יָלְדָה אִשְׁתְּךָ נְקֵבָה הֲרֵי הִיא מְקֻדֶּשֶׁת לִי, אֵינָהּ מְקֻדֶּשֶׁת. אִם הָיְתָה אֵשֶׁת חֲבֵרוֹ מְעֻבֶּרֶת וְהֻכַּר עֻבָּרָהּ, דְּבָרָיו קַיָּמִין, וְאִם יָלְדָה נְקֵבָה, מְקֻדֶּשֶׁת: