Matthew 19:4-7

He answered, “Have you not read that he who created them from the beginning made them male and female, 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’? So they are no longer two but one flesh. What therefore God has joined together, let not man separate.” They said to him, “Why then did Moses command one to give a certificate of divorce and to send her away?”