1 Kings 11:4-6

4For when Solomon was old, his wives turned his heart away 1to follow other gods; and 2his heart was not 3wholly devoted to the Lord his God, as the heart of his father David had been.

5For Solomon became a follower of 4Ashtoreth the goddess of the Sidonians, and of 56Milcom the abhorrent idol of the Ammonites.

6So Solomon did what was evil in the sight of the Lord, and did not follow the Lord fully, as his father David had done.