Mark 10:6-10
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 twain shall be one flesh: so then they are no more twain, but one flesh.
9What therefore God hath joined together, let not man put asunder.
10And in the house his disciples asked him again of the same matter.
(KJV)