וְנִקָּ֥ה הָאִ֖ישׁ מֵעָוֺ֑ן וְהָאִשָּׁ֣ה הַהִ֔וא תִּשָּׂ֖א אֶת־עֲוֺנָֽהּ׃ (פ)
און דער מאַן װעט זײַן רײן פֿון זינד, און יענע פֿרױ װעט טראָגן איר זינד.
Tze'enah Ure'enah
“The man shall be clear of guilt” [5:31]. Rashi and Imre Noam write. The husband should not say: I am guilty that she was given the bitter water to drink and she died. Therefore, the Torah says that the husband is free of any punishment. The verse also teaches us that when the woman drank the water and did not become impure, then she is as she was before for her husband.23Rashi, Numbers, 5:31.
Tze'enah Ure'enah
Imre Noam writes. It is written three times in the Torah “clear” [nikah]. This means, clear of sin, since there are three times where one’s sins are forgiven. There are three whose sins are forgiven. The first is when a person comes to greatness. Here, the Holy One forgives his sins. Someone who was sick and became well again, the Holy One forgives his sins. The Holy One also forgives a groom at his wedding his sins.24Imre Noam, Numbers, 5:31.
Tze'enah Ure'enah
Ramban and Bahya write. “The man shall be clear of guilt” [5:31], means, when the man never engaged in illicit sex and he also did not sleep with his wife from the time that she was suspected of secluding herself. Also, when somebody slept with his fiancיe, when she was still his fiancיe before the wedding, she is not given the water to drink. Even when his children engaged in illicit sex and he did not forbid it, his wife is not given the water to drink in the Temple. Similarly, when a priest marries a divorcee. That woman is not given the water to drink, because she has married through the sin. A divorcee is forbidden to marry a priest.25Ramban, Numbers, 5:20; Bahya, Numbers, 5:31.
Rashi
ונקה האיש מעון THEN SHALL THE MAN BE GUILTLESS FROM INIQUITY — This means, if the waters try her (have effect on her), he should not worry and say: “I have incurred guilt through her death!” — No, he is free from punishment. Another explanation is: As soon as he has made her drink the water and she is proved innocent she may lawfully remain with him as his wife, and he is free from sin in permitting this, but if he lives with her before this, he is not free, for a סוטה (a wife suspected of infidelity) is forbidden to her husband pending her trial (cf. Sifrei Bamidbar 21).