Deuteronomy 24:2-4

2If, after leaving his house, she goes and becomes another man’s wife, 3and the second man hates her, writes her a certificate of divorce, hands it to her, and sends her away from his house, or if he dies, 4then the husband who divorced her first may not remarry her after she has been defiled, for that is an abomination to the LORD. You must not bring sin upon the land that the LORD your God is giving you as an inheritance.