Mark 10:4-9

4 They said, “Moses permitted a man to write a certificate of divorce and send her away.”
5 “It was because your hearts were hard that Moses wrote you this law,” Jesus replied.
6 “But at the beginning of creation God ‘made them male and female.’a
7 ‘For this reason a man will leave his father and mother and be united to his wife,b
8 and the two will become one flesh.’cSo they are no longer two, but one flesh.
9 Therefore what God has joined together, let no one separate.”