1 Kings 11:1

Together with the daughter of Pharaoh— Pharaoh's daughter, as we have before remarked, is generally supposed to have been a proselyte to the Jewish religion, and therefore Solomon incurred no fault in marrying her. But in marrying so many women besides, and these of a different religion, he committed two sins against the law; one in multiplying wives, and another in marrying those of strange nations, who still retained their idolatry. And therefore the wise son of Sirach, amidst all the encomiums which he heaps upon Solomon, could not forget this great flaw in his character. See the note on 1 Kings 11:42.