2 Kings 3:1
Now Jehoram the son of Ahab began to reign over Israel in Samaria the eighteenth year of Jehoshaphat king of Judah, and reigned twelve years. Now Jehoram the son of Ahab began to reign over Israel in Samaria the eighteenth year of Jehoshaphat king of Judah, and reigned twelve years.
Jehoram reigned over Israel, the ten tribes, in Samaria, beginning in the eighteenth year of Jehoshaphat king of Judah and lasting twelve years. He succeeded his brother Ahaziah, who died childless. Though he removed his father's image of Baal, he continued in the sins of Jeroboam. During his reign his mother Jezebel was still alive and continued to exercise her evil influence over the affairs of the nation, and idolatrous customs were still practiced by many of the people.
The chapter this verse introduces presents a test of faith, showing that those who trust not in human ability, strength, or plans but in what God can do for and through them will see and realize His power at work. Victory in that battle comes not by human strength but by God, the mighty General of armies, who works in unexpected ways that cannot be mapped out in advance, for the glory of His own name. That test of faith is to be carefully studied because the same kind of test will be met again.