1. God rebukes Jeroboam (1-3)
A prophet from Judah came to King Jeroboam at Bethel while the king was making an offering. The new king was so paranoid about the spiritual influence of Judah that he invented a more convenient religion for Israel. But the LORD would one day raise up King Josiah who would completely overturn this religion. The priests would be killed and Jeroboam's altars desecrated. This happened just as God predicted through the prophet. (2 Kings 23:15-16) God judges idolatry.
2. The prophet obeys God (4-10)
Jeroboam's altar split open just as the prophet said. The king's hand also shriveled when he threatened the prophet. The prophet prayed for Jeroboam's hand to be restored and it was. The king invited the prophet for a meal but he refused. He declared to the idolatrous king that he would obey God in every detail.