Abijam began to rule over Judah in the eighteenth year of Jeroboam's reign in Israel.
References for 1 Kings 15:1
He reigned in Jerusalem three years. His mother was Maacah, the daughter of Absalom.
References for 1 Kings 15:2
He committed the same sins as his father before him, and his heart was not right with the LORD his God, as the heart of his ancestor David had been.
But for David's sake, the LORD his God allowed his dynasty to continue, and he gave Abijam a son to rule after him in Jerusalem.
References for 1 Kings 15:4
For David had done what was pleasing in the LORD's sight and had obeyed the LORD's commands throughout his life, except in the affair concerning Uriah the Hittite.
There was war between Abijam and Jeroboam throughout Abijam's reign.
References for 1 Kings 15:6
The rest of the events in Abijam's reign and all his deeds are recorded in The Book of the History of the Kings of Judah. There was constant war between Abijam and Jeroboam.