2 Kings 10:25
And it came to pass, as soon as he had made an end of offering the burnt offering, that Jehu said to the guard and to the captains, Go in, and slay them; let none come forth. And they smote them with the edge of the sword; and the guard and the captains cast them out, and went to the city of the house of Baal.
Cross-reference
2 Kings 23:20 records Josiah slaughtering idolatrous priests on their altars — another purge of false worship like Jehu's.
In Exodus 32:27, Moses commands the Levites to kill idolaters — mirrors Jehu's slaughter of Baal priests.
Deuteronomy 13:6-11 commands death for those who entice to worship other gods — Jehu carries out this law against Baal servants.
In Ezekiel 9:5-7, God orders executioners to strike down unmarked idolaters without pity — mirroring Jehu's commanded slaughter of Baal's prophets.
In 1 Kings 18:40, Elijah does the same — seizes Baal's prophets and slaughters them, commanding 'let not one escape.'
2 Chronicles 23:17 describes tearing down Baal's house and killing his priest — directly parallel to Jehu's destruction of Baal's temple and prophets.