Mark 10:2-9

The Pharisees approached and asked, “Is it lawful for a husband to divorce his wife?” They were testing him. He said to them in reply, “What did Moses command you?” They replied, “Moses permitted him to write a bill of divorce and dismiss her.” But Jesus told them, “Because of the hardness of your hearts he wrote you this commandment. But from the beginning of creation, ‘God made them male and female. For this reason a man shall leave his father and mother [and be joined to his wife], and the two shall become one flesh.’ So they are no longer two but one flesh. Therefore what God has joined together, no human being must separate.”