Quote from ACIM Text Chapter 6, Section 5 - The Only Answer.

That is why the Holy Spirit never commands. To command is to assume inequality, which the Holy Spirit demonstrates does not exist. Fidelity to premises is a law of mind, and everything God created is faithful to His laws. Fidelity to other laws is also possible, however, not because the laws are true, but because you made them. What would be gained if God proved to you that you have thought insanely? Can God lose His Own certainty? I have frequently said that what you teach you are. Would you have God teach you that you have sinned? If He confronted the self you made with the truth He created for you, what could you be but afraid? You would doubt your right mind, which is the only place where you can find the sanity He gave you.