Those who deny the truth ask, "Why has no Sign been sent down to him by his Lord?" Say, "God lets go astray those whom He wills and guides to Himself those who turn to Him, 27 those who believe, and whose hearts find comfort in the remembrance of Allah. Is it not with the remembrance of Allah that hearts are satisfied. 28 Those who believe (in the Oneness of Allah - Islamic Monotheism), and work righteousness, Tuba (it means all kinds of happiness or name of a tree in Paradise) is for them and a beautiful place of (final) return. 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 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