Is it a condition that the declaration of permissibility be in the heart for the ruling of disbelief to apply?

Question:
Honorable Shaykh, may Allah reward you. Is it a condition that the declaration of permissibility be in the person, such that one who declares something permissible in his heart is not declared a disbeliever?

Answer:
We do not know about hearts; only Allah knows about them. We only rule based on what appears from a person in his words or his actions. As for what is in the hearts, that is for Allah the Exalted and Majestic; it is not our concern. If a person displays Islam, we accept it from him, even if he is a hypocrite in his heart. The Messenger (peace and blessings be upon him) accepted Islam from the hypocrites, and they are in the lowest depth of the Fire. He dealt with them based on their outward appearance. So we have nothing but the outward appearance.