Deuteronomy 17:17

Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.

And unto David were sons born in Hebron: and his firstborn was Amnon, of Ahinoam the Jezreelitess; And his second, Chileab, of Abigail the wife of Nabal the Carmelite; and the third, Absalom the son of Maacah the daughter of Talmai king of Geshur; And the fourth, Adonijah the son of Haggith; and the fifth, Shephatiah the son of Abital; And the sixth, Ithream, by Eglah David's wife. These were born to David in Hebron.

But king Solomon loved many strange women, together with the daughter of Pharaoh, women of the Moabites, Ammonites, Edomites, Zidonians, and Hittites: Of the nations concerning which the LORD said unto the children of Israel, Ye shall not go in to them, neither shall they come in unto you: for surely they will turn away your heart after their gods: Solomon clave unto these in love. And he had seven hundred wives, princesses, and three hundred concubines: and his wives turned away his heart. For it came to pass, when Solomon was old, that his wives turned away his heart after other gods: and his heart was not perfect with the LORD his God, as was the heart of David his father.

Did not Solomon king of Israel sin by these things? yet among many nations was there no king like him, who was beloved of his God, and God made him king over all Israel: nevertheless even him did outlandish women cause to sin.

And did not he make one? Yet had he the residue of the spirit. And wherefore one? That he might seek a godly seed. Therefore take heed to your spirit, and let none deal treacherously against the wife of his youth.

And said, For this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh?