Sforno on Numbers 5:15/ספורנו על במדבר ה׳:ט״ו

1והביא האיש את אשתו, we do not say that seeing that her husband had sat by silently while his wife had behaved unchastely, accusing her in his heart without saying a word, that this is proof of the husband’s bad attitude and we should therefore ignore his jealousy seeing he had allowed matters to get to the point where she had slept with another man; neither do we ignore his jealousy if she had not given him cause as something not worth paying attention to. We still subject her to the destruction (erasing) of the name of G’d (in the procedure the Torah will presently describe) in order to reveal the truth.