1Cor 7:11

“But and if she depart,.... This is said, not as allowing of such a departure, which only in case of fornication is lawful; but supposing it a fact, that a woman cannot be prevailed upon to stay with her husband, but actually forsakes him upon some difference arising between them, let her remain unmarried: she ought not to marry another man; her departure does not make the marriage void; nor is it to be made void by any difference between them, either on religious or civil accounts, only in case of adultery; and therefore, if upon such separation she marries, she is guilty of adultery: or be reconciled to her husband; which is rather to be chosen, than to remain separate, though unmarried; if she has given the offence, and is the cause of the separation, she ought to acknowledge it, and ask forgiveness of her husband, and return to him and live in peace with him; and if the fault is on his side, she ought to make use of all proper methods to convince him of it, bring him into good temper, forgive any injury done her, and live peaceably and comfortably together: and let not the husband put away his wife; as the Jews were wont to do, upon every trifling occasion; See Gill on Mat 5:31, Mat 5:32”

“But, and if she depart - He puts the case as probable, because it was frequent, but lays it under restrictions. Let her remain unmarried - She departs at her own peril; but she must not marry another: she must either continue unmarried, or be reconciled to her husband. And let not the husband put away his wife - Divorces cannot be allowed but in the case of fornication: an act of this kind dissolves the marriage vow; but nothing else can. It is a fact that, among the Jews, the wife had just as much right to put away her husband as the husband had to put away his wife. As divorces were granted, it was right that each should have an equal power; for this served as a mutual check.”

“But and if she depart--or "be separated." If the sin of separation has been committed, that of a new marriage is not to be added (Mat 5:32). be reconciled--by appeasing her husband's displeasure, and recovering his good will. let not . . . husband put away . . . wife--In Mat 5:32 the only exception allowed is, "saving for the cause of fornication."”