Matthew 5:31-32 It was also said, ‘Whoever divorces his wife, let him give her a certificate of divorce.’ (32) But I say to you that everyone who divorces his wife, except on the ground of sexual immorality, makes her commit adultery, and whoever marries a divorced woman commits adultery.
Matthew 19:3-9 And Pharisees came up to him and tested him by asking, “Is it lawful to divorce one's wife for any cause?” (4) He answered, “Have you not read that he who created them from the beginning made them male and female, (5) and said, ‘Therefore a man shall leave his father and his mother and hold fast to his wife, and the two shall become one flesh’? (6) So they are no longer two but one flesh. What therefore God has joined together, let not man separate.” (7) They said to him, “Why then did Moses command one to give a certificate of divorce and to send her away?” (8) He said to them, “Because of your hardness of heart Moses allowed you to divorce your wives, but from the beginning it was not so. (9) And I say to you: whoever divorces his wife, except for sexual immorality, and marries another, commits adultery.
Mark 10:2-12 And Pharisees came up and in order to test him asked, “Is it lawful for a man to divorce his wife?” (3) He answered them, “What did Moses command you?” (4) They said, “Moses allowed a man to write a certificate of divorce and to send her away.” (5) And Jesus said to them, “Because of your hardness of heart he wrote you this commandment. (6) But from the beginning of creation, ‘God made them male and female.’ (7) ‘Therefore a man shall leave his father and mother and hold fast to his wife, (8) and the two shall become one flesh.’ So they are no longer two but one flesh. (9) What therefore God has joined together, let not man separate.” (10) And in the house the disciples asked him again about this matter. (11) And he said to them, “Whoever divorces his wife and marries another commits adultery against her, (12) and if she divorces her husband and marries another, she commits adultery.
Luke 16:18 Everyone who divorces his wife and marries another commits adultery, and he who marries a woman divorced from her husband commits adultery.