The Unbelievers say: "Why is not a sign sent down to him from his Lord?" Say: "Truly Allah leaveth, to stray, whom He will; But He guideth to Himself those who turn to Him in penitence,- 27 They are those who believe and whose hearts find rest in the remembrance of Allah. Lo! in the remembrance of Allah hearts do find rest. 28 Those who believe and do the right, have happiness, and an excellent resting place. 29 Thus We have sent you to a people, before whom other peoples have passed away, so that you may recite to them what We have revealed to you. Yet they deny the Gracious God. Say, "He is my Lord; there is no god but He. In Him I put my trust and to Him I shall return." 30 And if there was any qur'an by which the mountains would be removed or the earth would be broken apart or the dead would be made to speak, [it would be this Qur'an], but to Allah belongs the affair entirely. Then have those who believed not accepted that had Allah willed, He would have guided the people, all of them? And those who disbelieve do not cease to be struck, for what they have done, by calamity - or it will descend near their home - until there comes the promise of Allah. Indeed, Allah does not fail in [His] promise. 31