In the Book of Malachi, the new Idolatry was not the worshiping of false gods like Baal, but rather the Idolatry of half-hearted worship of the True God, Yahweh.

This Idolatry created complacency and lukewarm devotion to God that was expressed in polluted worship, inadequate sacrifice, glorification of evil, and oppression of the vulnerable. All while expressing ingratitude toward God and blaming him for injustice.

In an age of complacency and polluted worship, there is a remnant that fears the LORD and stays faithful by keeping a book of remembrance.