Deuteronomy 24:1

24:1 When a man hath taken a wife, and married her, and it come to pass that she find no favour in his eyes, because he hath found some uncleanness in her: then let him write her a bill of divorcement, and give [it] in her hand, and send her out of his house.

Matthew 5:31-32

5:31 It hath been said, Whosoever shall put away his wife, let him give her a writing of divorcement: 5:32 But I say unto you, That whosoever shall put away his wife, saving for the cause of fornication, causeth her to commit adultery: and whosoever shall marry her that is divorced committeth adultery.