“King Hazael of Aram oppressed Israel all the days of King Jehoahaz. But Yahweh was gracious to them. He had compassion on them. He turned toward them, because of his covenant with Abraham, Isaac, and Jacob. He would not destroy them. Nor has he banished them from his presence until now.”
Actually Yahweh had Elisha anoint King Hazael of Arameans. His oppression of the Israelites was there punishment as outlined in 1 Kings, chapter 19 and confirmed here in 2 Kings, chapter 8. However, Yahweh had compassion on Israel despite their leaders and their sins. He would not let them be destroyed because of the covenant with Abraham, Isaac, and Jacob.
“The anger of Yahweh was kindled against Israel. He gave them repeatedly into the hand of King Hazael of Aram, and then into the hand of King Ben-hadad son of King Hazael. But King Jehoahaz entreated Yahweh. Yahweh heeded him. Yahweh saw the oppression of Israel. He saw how the king of Aram oppressed them. Therefore Yahweh gave Israel a savior, so that they escaped from the hand of the Arameans. The people of Israel lived in their homes as formerly. Nevertheless they did not depart from the sins of the house of Jeroboam, which he caused Israel to sin, but walked in them. The sacred poles also remained in Samaria. Thus King Jehoahaz was left with an army of not more than fifty horsemen and ten chariots with ten thousand footmen. The king of Aram had destroyed them. He made them like the dust at threshing.”
If King David had problems with the Philistines along the west coast, these 9th century BCE Israelite kings always seem to be in battle with the Arameans, in the northeast. Yahweh was continually upset with the Israelite kings. This may be partly due to the bias of the biblical author. There is a little confusion here since King Hazael had killed King Ben-hadad to take over the Arameans, why would his son have the same name as the king he killed? The answer might be that they were friends when he was born. King Jehoahaz asked Yahweh to help him in his battle with the Arameans. Yahweh was kind to the Israelites since he saw how they were suffering. He was going to send a savior or liberator, and that would be King Jeroboam II. Even after saving them from the Arameans, the Israelites continued to worship the sacred poles in Samaria. Then King Jehoahaz was left with 50 horsemen, 10 chariots, and 10,000 foot soldiers. That does not seem too bad. However, the Arameans destroyed them like the scattered dust.