 So, in respect to the crucial question of how we are to know whether a revelation is genuine, we are supposed to use reason and the canons of probability to judge. Locke claims that if the boundaries between faith and reason are not clearly marked, then there will be no place for reason in religion and one then gets all the “extravagant Opinions and Ceremonies, that are to be found in the religions of the world…” (IV.18.11, N: 696).