Is it true that Allah won't forgive Blaspheme against the prophet Muhammad Mustafa sallallahu alaihi wasallam even if he ask for forgiveness and sincerely repent. If a person always suspect or doubts that he will utter kufriya words against prophet Muhammad Mustafa sallallahu alaihi salaam and than regret and repent it sincerely will Allah forgive him what if the person is slightly mentally ill he is knowledgeable but he detest to utter such words what if he utter those words and ask for forgiveness will Allah forgive him. If he he stop doing the blasphemy will Allah forgive him

If he repent sencerely and dont repeat it will allah forgive him insha allah