And those who disbelieve say: "Why is not a sign sent down to him (Muhammad SAW) from his Lord?" Say: "Verily, Allah sends astray whom He wills and guides unto Himself those who turn to Him in repentance." 27 Those who believe (in the Oneness of Allah - Islamic Monotheism), and whose hearts find rest in the remembrance of Allah, Verily, in the remembrance of Allah do hearts find rest. 28 So those who believe (in the message of the Truth) and do good are destined for happiness and a blissful end. 29 That is how We have sent you to a people before whom many a people have come and gone, so that you may announce to them whatever We have revealed to you. But they do not believe in Ar-Rahman. Tell them: "He is my Lord. There is no other god but He. In Him have I placed my trust, and to Him is my reversion." 30 And if there were a Qur'an whereby the mountains could be moved or whereby the earth could be traversed or whereby the dead could be spoken to, it would be in vain. Aye! the affair belongeth to Allah entirely. Have not then those who believe yet known? that had Allah willed, He would have guided all mankind! And a rattling adversity ceaseth not to befall those who disbelieve for that which they have wrought or to alight nigh unto their habitation until Allah's promise cometh; verily Allah faileth not the tryst. 31