Rashi explains the juxtaposition of the laws of sotah, the errant wife, to the preceding passage, which addresses the laws of Matnos Kehunah, the Priestly gifts. The connection between the two passages is that if one withholds the gifts that rightfully belong to the Kohen, he will have to confront the Kohen when he is required to bring his wife, the sotah, to him. Simply, this means that if one does not go to the Kohen out of his own free-will, he will be compelled to go out of a sense of urgency and necessity. This makes sense in regard to the husband. His obstinacy in refusing to give the Kohen his due is the catalyst for the husband to go to the Kohen against his will. What about his wife? She certainly should have a choice in the matter: whether to sin or not. It seems that because of the husband’s non-action, she ends up as a sotah. Why is this?
Horav Baruch Shimon Schneerson, z.l., Rosh HaYeshivah of Yeshivas Tchebin offers a practical response. He posits that the husband is not refusing the Kohen his due out of a sense of evil. It is not as if he steals the Kohen’s gifts by refusing to give them Terumah. In fact, this man views himself as a tzaddik, a righteous man, who is acting correctly, even righteously, by not giving the Kohen the Terumah. He ascribes to Chazal’s statement criticizing one who gives Terumah to an illiterate Kohen. He refuses to give the Kohen his due because he feels the Kohen is not worthy to receive this gift.
This occurs in regard to every Kohen. “Our” husband finds fault in every Kohen — this one is illiterate, the other one is not pious enough, while yet a third is not virtuous, and so on and so forth. In short, he denigrates the Priesthood. Anyone living in a house where the honor of Torah is vilified, in which Torah scholars become a mockery and their lifestyle disparaged, will certainly develop a disdain for Torah and its commandments. It is no wonder that this person’s wife violated the boundaries of matrimony and was disloyal to her husband. Chazal teach us that “aveirah goreres aveirah,” a sin causes another sin. One who falls into the stranglehold of sin will regrettably compound his transgressions with continued sin, because one sin leads to another. This is especially true when one attempts to justify his evil by considering it to be a mitzvah.