1 Kings 11:5-7

11:5 Solomon worshiped the Sidonian goddess Astarte and the detestable Ammonite god Milcom. 11:6 Solomon did evil in the Lord’s sight; he did not remain loyal to the Lord, like his father David had. 11:7 Furthermore, on the hill east of Jerusalem Solomon built a high place for the detestable Moabite god Chemosh and for the detestable Ammonite god Milcom.

1 Kings 11:2

11:2 They came from nations about which the Lord had warned the Israelites, “You must not establish friendly relations with them! If you do, they will surely shift your allegiance to their gods.” But Solomon was irresistibly attracted to them.

1 Kings 1:13

1:13 Visit King David and say to him, ‘My master, O king, did you not solemnly promise your servant, “Surely your son Solomon will be king after me; he will sit on my throne”? So why has Adonijah become king?’