Quoting from What We Can’t Not Know: “A paraphrase of the Second Commamdment might be “You shall not use empty speech in connection with God.” … To say this is one of the things we can’t not know–that it belongs not only to biblical injunction but to natural law–is to say that we naturally understand certain things about the relation of speech to reality, a theme to which we return in the Eighth Commandment. Even a liar’s speech expressing something true; it may not tell us the state of the world, but it tells us the state of his heart. What empty God-talk tells us is that where there ought to be God, there is emptiness.”