What do all the religions of the world trace back to?
All the religions of the world trace their roots back to the Tower of Babel. At that early post-flood gathering in the valley of Shinar, pagan idolatrous religion began, and every cult or idolatrous system since then can be traced to that same origin.
Les explains that the early post-flood group gathered in the valley of Shinar on the Euphrates River and built the Tower of Babel. At that point in human history, all pagan idolatrous religion began. He notes that any true cult, even if it uses some Scripture, has doctrine that roots right back to Babel, and all world religions trace their roots there. This is what Paul meant in 2 Thessalonians when he wrote that the mystery of iniquity was already working—it has worked since the scattering from Babel and has constantly opposed true worship of Jehovah God. Israel's nemesis was idolatry, such as Baal worship and Moloch, and Paul confronted similar idolatrous gods in the Gentile world.