Balaam could not curse Israel. So he taught their enemies how to make Israel curse itself.
Before leaving, the prophet gave Balak and the Midianite princes a final piece of advice: send your most beautiful daughters to the Israelite camp. Let the young men fall in love. And when they are desperate enough to do anything to keep these women, have the women demand one thing—that the Hebrews abandon the God of Israel and worship the gods of Midian. This, Balaam said, was the only way to provoke God's anger against His own people.
It worked. The Midianite women entered the camp, and the Hebrew men were overwhelmed. The women consented to stay—on one condition. They told the young men that their God was foreign and exclusive, that everyone else worshipped the local gods, and that if they truly loved them, they would do the same. One by one, the men gave in. They ate forbidden food. They bowed before foreign altars. The corruption swept through the entire army like a plague.
Even Zimri, the head of the tribe of Simeon, openly took a Midianite woman named Cozbi, daughter of the Midianite prince Sur. When Moses addressed the assembly and urged repentance, Zimri stood up and mocked him to his face. He called Moses a tyrant and declared his right to worship whatever gods he chose and marry whomever he pleased.
The people were paralyzed. Moses would not escalate. But Phinehas—the grandson of Aaron, a young man of extraordinary courage—refused to let defiance become precedent. He walked into Zimri's tent and killed both Zimri and Cozbi with a single javelin thrust (Numbers 25:7-8). Other young men who shared his conviction followed his example, striking down the worst offenders. A divine plague consumed the rest. Twenty-four thousand Israelites died. Phinehas's act of zealotry stopped the destruction—and earned him an eternal covenant of peace from God.