Sifrei Bamidbar 15

¹(Bamidbar 5:22) "to swell the belly and to make fall the thigh": R. Yossi Haglili says: This refers to the belly and the thigh of the adulterer. You say the belly and the thigh of the adulterer; but (perhaps it refers to) the belly and the thigh of the adulteress! — (This cannot be, for) [5:21] "… causing your thigh to fall and your belly to swell" already refers to the adulteress. How, then, am I to understand "to swell the belly and to make fall the thigh"? As referring to the adulterer, Scripture apprising us that just as punishment overtakes her, so, it overtakes him. Now does this not follow a fortiori, viz.: If re the attribute of punishment, the "weaker" attribute (of the Holy One Blessed be He), if one brings misfortune to his neighbor, he suffers likewise, then re the attribute of benefaction, (the stronger attribute, if one bring benefit to his neighbor,) how much more so (is he benefitted himself!) (Ibid. 22) "and the woman shall say 'Amen,' 'Amen.'": "Amen" that I have not become unclean; "Amen" that I will not become unclean, (in which instance the bitter waters operate retroactively). These are the words of R. Meir. And the sags do not agree, (but they say) "Amen" that I have not become unclean (i.e., acceptance of the oath) and ("Amen" that) if I have become unclean, they (the waters) should enter her (i.e., acceptance of the curse). "Amen" in respect to this man (the suspected adulterer); "Amen" in respect to any other man; "Amen" when betrothed — "Amen" when married; "Amen" when awaiting levirate marriage — "Amen" after levirate marriage. This is the rule: For a woman to be lived with and (thereby) to be forbidden (to her husband), the stipulated conditions must be those of that time (i.e., while she is still married to him [and not, e.g., before betrothal or after divorce]). ²Since oaths are mentioned in the Torah generically, and in one case (that of sotah) it is specifically indicated that the oath must be accompanied by a curse, I derive that the same must obtain with all oaths in the Torah. Since in one case (that of sotah) it is specifically indicated that the oath must be administered under the Name "yod-keh," I derive the same for all oaths in the Torah. And since oaths are mentioned generically in the Torah, and of one of them (sotah), it was specified that it be (answered) with "Amen," so, I derive that the same holds true for all oaths in the Torah. Abba Channan says in the name of R. Eliezer: ("Amen" is repeated here) to include the oath administered by the judges, that it be answered by "Amen." For if it is not answered by "Amen," it is rendered a "vain oath" (in the name of the L-rd.) Since oaths are mentioned generically in the Torah, and in one case (sotah) it is specifically indicated that a previous oath (i.e., an oath for a previous matter) can be "rolled" onto it (e.g., When she answers "Amen" to not having been defiled by this man, she also answers "Amen" to not having been defiled by another, etc.), I derive the same for all of the oaths in the Torah. Now does this not follow a fortiori, viz.: If in the instance of sotah, where no previous claim has been made against her, a previous oath is "rolled" onto her, then, in instances of thefts, where previous claims have been made, how much more so may previous oaths be "rolled" onto them!