Mark 10:2-9

2And the Pharisees came to him, and asked him, Is it lawful for a man to put away his wife? tempting him.

3And he answered and said to them, What did Moses command you?

4And they said, Moses permitted to write a bill of divorcement, and to put her away.

5And Jesus answered and said to them, For the hardness of your heart he wrote you this precept.

6But from the beginning of the creation God made them male and female.

7For this cause shall a man leave his father and mother, and cleave to his wife;

8And they two shall be one flesh: so then they are no more two, but one flesh.

9What therefore God hath joined together, let not man separate.