An uninvited thought is not a belief

This is the knot most people are stuck in, so let us untie it first.

A thought that arrives without being asked for is not a belief. It is not a choice, and it is not a quiet confession of what you secretly want. It is an event in your head. You authored it about as much as you author a sneeze.

The Companions came to the Prophet, peace be upon him, with exactly this. They said they found things in themselves that they could not bring themselves to say out loud. He did not tell them their faith was in danger. He told them that being horrified by it was itself the mark of faith.