Those who have been assisted by God (however they see or understand what "God" is or means) are in no need of assurance as to that help being real. It's real.

You don't have to be a Christian to receive that help. You can belong to any religion. You can even belong to no particular religion.

It's people who expect or demand exclusivity of membership in this or that religion, not God. God is Universal, and predates all religions. (in my opinion)

Religions are the result of the various attempts of people throughout history to deal with and articulate something that is simply beyond their understanding. The mind cannot grasp it.

In the case of a person who thinks he IS his mind... (Bill?) ...this is a conundrum that seems unacceptable. ;-)