The unbelievers say, 'Why has a sign not been sent down upon him from his Lord?' Say: 'God leads astray whomsoever He will, and He guides to Him all who are penitent.' 27 Those who believe and find peace in their hearts from the contemplation of God: Surely there is peace of heart in the contemplation of God!" 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 We have sent you to a nation before whom there lived many nations so that you would read to them what We have revealed to you. They still deny the existence of the Beneficent God. Say, "He is my Lord besides whom there is no other God. I trust Him and turn to Him in repentance." 30 And if there had been a Quran with which mountains could be moved (from their places), or the earth could be cloven asunder, or the dead could be made to speak (it would not have been other than this Quran). But the decision of all things is certainly with Allah. Have not then those who believe yet known that had Allah willed, He could have guided all mankind? And a disaster will not cease to strike those who disbelieve because of their (evil) deeds or it (i.e. the disaster) settle close to their homes, until the Promise of Allah comes to pass. Certainly, Allah does not fail in His Promise. 31