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 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 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 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