Will the doubter be tormented in this world, or will he die in disbelief, based on the Hadith which states that it will be said to him in the grave: "Upon doubt you were, and upon it you died, and upon it you shall be resurrected, if Allah wills"?

Whoever doubts Allah, or His angels, or His messengers, or the Resurrection, or Paradise, or Hell, or any of the fundamentals of faith, is a disbeliever (kafir), as stated in the Almighty's saying: (Did you disbelieve in Him who created you from dust, then from a sperm-drop, then fashioned you into a man?). And the Prophet, peace and blessings be upon him, said: "No servant meets Allah with these two [testimonies of faith] without doubting them, except that he enters Paradise." And whoever dies upon doubt will abide eternally in Hell, for Allah accepts nothing from His servant except certainty.