A single Supreme Court test helped drive 50 years of fights over prayer, the Bible, and religious symbols in public life and most people never learned its name. We unpack how rulings like Engel v. Vitale and Lemon v. Kurtzman changed the rules for schools and government spaces, why the Lemon test got cited thousands of times, and how it fueled everything from nativity scene battles to challenges over crosses and the Ten Commandments. If you’ve ever wondered what the First Amendment really say...