Those who have rejected (the message of Muhammad) say: "Why has no sign been sent down upon him from his Lord?" Tell them: "Allah lets go astray those whom He wills, and guides to Himself those who turn 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 Those who believe and do the right, have happiness, and an excellent resting place. 29 As such, We have sent you forth to a nation before whom others have passed away in order that you recite to them what We have revealed to you. Yet they disbelieve the Merciful. Say: 'He is my Lord. There is no god except He. In Him I have put my trust, and to Him I turn' 30 Had it been possible for a Lecture to cause the mountains to move, or the earth to be torn asunder, or the dead to speak, (this Qur'an would have done so). Nay, but Allah's is the whole command. Do not those who believe know that, had Allah willed, He could have guided all mankind? As for those who disbelieve, disaster ceaseth not to strike them because of what they do, or it dwelleth near their home until the threat of Allah come to pass. Lo! Allah faileth not to keep the tryst. 31