Deuteronomy 24:1-4

24:1 If a man marries a woman and she does not please him because he has found something offensive in her, then he may draw up a divorce document, give it to her, and evict her from his house. 24:2 When she has left him she may go and become someone else’s wife. 24:3 If the second husband rejects her and then divorces her, gives her the papers, and evicts her from his house, or if the second husband who married her dies, 24:4 her first husband who divorced her is not permitted to remarry her after she has become ritually impure, for that is offensive to the Lord. You must not bring guilt on the land which the Lord your God is giving you as an inheritance.

Mark 10:4

10:4 They said, “Moses permitted a man to write a certificate of dismissal and to divorce her.”