1 Kings 1:7

1:7 He collaborated with Joab son of Zeruiah and with Abiathar the priest, and they supported him.

1 Kings 1:18

1:18 But now, look, Adonijah has become king! But you, my master the king, are not even aware of it!

1 Kings 2:28

2:28 When the news reached Joab (for Joab had supported Adonijah, although he had not supported Absalom), he ran to the tent of the Lord and grabbed hold of the horns of the altar.