The ruling on one who performs the obligatory acts but doubts the validity of Islam

Question:
May Allah reward you. The questioner, Abdullah, says: Peace be upon you, and Allah’s mercy and blessings. Is the Islam or faith of one who prays and fasts valid, if he doubts the validity of Islam for many reasons, and only performs the obligatory acts, while his inner state says: If the message of Islam is true, then here I am having performed some of what is required of me; and if it is not true, and there is no religion and no reckoning, then I will lose nothing.

Answer:
If he says this out of doubt and obsessive whispers, if he says it out of obsessive whispers, then he must seek refuge in Allah from the accursed Shaytan. If obsessive whispers occur in the heart and he does not speak them or act upon them, they do not harm him, as the Messenger (peace and blessings be upon him) said: and acts upon them. If this is a matter of obsessive whispers, then he must reject them, not speak them, not act upon them, and seek refuge in Allah from the accursed Shaytan, and they will go away from him, if Allah wills. But if this is not a matter of obsessive whispers, but rather doubt in his heart and in his creed, then he commits disbelief by that, may Allah protect us from it, and his faith becomes invalid. So the one who holds this opinion is not a believer. Yes.