Deuteronomy 24:4
Her former husband, which sent her away, may not take her again to be his wife, after that she is defiled; for that is abomination before the LORD: and thou shalt not cause the land to sin, which the LORD thy God giveth thee for an inheritance.
Moses commanded and wrote this passage as the human author of the Pentateuch, as Jesus affirmed when speaking of what Moses commanded and wrote concerning divorce. The former husband who sent his wife away may not take her back again to be his wife after she has been married to another man. Such a return is an abomination before the Lord, bringing shame and confusion.
In its setting the passage describes a restricted permission under the law of Moses for a husband to divorce a wife who did not please him by giving her a bill of divorcement, a written certificate, and sending her away, and it permits the divorced woman to marry again. That permission for divorce and remarriage was a provision Moses allowed because of the hardness of Israel's hearts, a condition God suffered and tolerated because of human blindness and hardness of heart. It was a concession, not the original divine plan and principles for marriage and family life; God tolerated such conditions to let people learn His will but requires repentance when light comes.
As a social law given to Israel, its specific requirements are not binding as law on other nations, but its underlying principles remain binding. In the light of Christ's teaching, a man may divorce his wife and marry again only in the case of fornication; otherwise he commits adultery, and a man who marries a woman guilty of fornication also commits adultery. Marrying a second and a third time is permitted and approved, for the special instruction about remarriage in the books of Moses came through Christ; therefore after a husband or wife dies the surviving companion may truly love another person equally with the first and be joined in marriage, and that marriage can be divine. The prohibition checks the ruinous practice of remarriage between the former spouses, expresses God's enduring view of this marriage relation, and calls those involved to repentance and purity.