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 Who have believed and whose hearts have rest in the remembrance of Allah. Verily in the remembrance of Allah do hearts find rest! 28 [and so it is that] they who attain to faith and do righteous deeds are destined for happiness [in this world] and the most beauteous of all goals [in the life to come]!" 29 Thus We have sent thee unto a community before whom other communities have passed away, in order that thou mayest recite unto them that which We have revealed unto thee; yet they disbelieve in the Compassionate. Say thou: He is my Lord, there is no god but he; on Him I rely, and unto Him is my return in penitence. 30 And what would have happened were a Qur'an to be revealed wherewith mountains could be set in motion, or the earth cleft, or the dead made to speak? (To show such signs is not at all difficult for) everything rests entirely with Allah. So, do not the people of faith (still look forward to such a sign in response to the demand of the unbelievers and) despair as a result of knowing that had Allah so willed, He could have guided all to the Truth. Misfortune continues to afflict the unbelievers on account of their misdeeds, or to befall on locations close to their habitation. This will continue until Allah's promise (of chastisement) is fulfilled. Indeed Allah does not go back upon His promise. 31