And those who disbelieved say, "Why has a sign not been sent down to him from his Lord?" Say, [O Muhammad], "Indeed, Allah leaves astray whom He wills and guides to Himself whoever turns back [to Him] - 27 Those who have believed and whose hearts are assured by the remembrance of Allah. Unquestionably, by the remembrance of Allah hearts are assured." 28 "For those who believe and work righteousness, is (every) blessedness, and a beautiful place of (final) return." 29 Thus have we sent thee amongst a People before whom (long since) have (other) Peoples (gone and) passed away; in order that thou mightest rehearse unto them what We send down unto thee by inspiration; yet do they reject (Him), the Most Gracious! Say: "He is my Lord! There is no god but He! On Him is my trust, and to Him do I turn!" 30 If there were a Qur'an with which mountains were moved, or the earth were cloven asunder, or the dead were made to speak, (this would be the one!) But, truly, the command is with Allah in all things! Do not the Believers know, that, had Allah (so) willed, He could have guided all mankind (to the right)? But the Unbelievers,- never will disaster cease to seize them for their (ill) deeds, or to settle close to their homes, until the promise of Allah come to pass, for, verily, Allah will not fail in His promise. 31