Commentary for Numbers 5:22

לצבות בטן is the same as לְהַצְבּוֹת בטן (the verb being the Hiphil infinitive). This is the usage of the Patach: that the “lamed” has it as its vowel instead of the ה having it (viz., that it is a contraction of לה). Similar is (Exodus 13:21) לַרְאתכם הדרך and (Deuteronomy 1:33) לַנְחֹתָם בדרך אשר הלכו בה (which are equivalent to לְהַרְאֹתְכֶם and לְהַנְחֹתָם). And so, too, in this verse, לַנְפִּל ירך, which is the same as לְהַנְפִּיל ירך. The meaning is: that the waters cause the belly to swell, and cause the thigh to fall.

אמן אמן. The reason she has to repeat the word אמן is that she thereby acknowledges that she accepts the verdict both if it is in her favour and if it would incriminate her.

For the curse. Tosafos in the first chapter of Kiddushin (27b) explain that one could have easily derived “for the curse … for the oath … from this husband … from a different husband” from one Amein, since it refers to all that was said in this passage. The curse and the oath are written explicitly here, while the Torah also writes “while you were married to your husband” (v. 20) which implies both this husband and another husband. Thus the other Amein refers to women who were engaged or waiting for levirate marriage who are not mentioned in this passage, and Rashi has condensed his words. This raises a difficulty: If Rashi’s opinion was so, he should have said “Amein if from this husband, if from different husband; Amein for the curse and for the oath. However, Rashi elaborated where he should have been brief and said the word Amein twice — Amien for the curse and Amein for the oath — and similarly Amein if from this husband, Amein if from a different husband. Thus it is certain that Rashi here means to explain that these two Ameins are needed for what was mentioned, one for the curse and one for the oath, and similarly one Amein if from this husband and one if from a different husband. And there is no difficulty that there are only two Ameins here, for one may answer that one can derive two things from the one Amein. Rashi here did not want to explain [that it referred to] the cases of the betrothed woman etc., because they are not implied by the verse, only through oral tradition like most of the Oral Law. Rashi only explains the language of the Torah — and it should have written Amein and Amein with a vav if it was adding another case. (R. Y. Triosh)