Joined himself - i. e., by taking part in the sacrificial meals as described in the last verse. Compare Exodus 34:15; 1 Corinthians 10:18. The worship of Baal was attended with the grossest impurity, and indeed partly consisted in it Hosea 4:14; Hosea 9:10.
Baal-peor - i. e., the Baal worshipped at Peer, the place mentioned in Numbers 23:28 (compare Baal-meon, Numbers 32:38). (The identification of this god with Chemosh in Numbers 21:29 is now given up.)