all that is because allah is the reality and it is he who revives the dead and he has power over all things and because the hour is bound to come there is no doubt in it and allah will resurrect those who are in the graves.
ذلك بأن الله هو الحق وأنه يحيي الموتى وأنه على كل شيء قدير وأن الساعة آتية لا ريب فيها وأن الله يبعث من في القبور