And those who disbelieved say, "Why has a sign not been sent down to him from his Lord?" Say, [O Muhammad], "Indeed, Allah leaves astray whom He wills and guides to Himself whoever turns back [to Him] - 27 Who have believed and whose hearts have rest in the remembrance of Allah. Verily in the remembrance of Allah do hearts find rest! 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 Thus have We raised thee [O Muhammad] as Our Apostle amidst a community [of unbelievers] before whose time [similar] communities have come and gone, so that thou might propound to them what We have revealed unto thee: for [in their ignorance] they deny the Most Gracious! Say: "He is my Sustainer. There is no deity save Him. In Him have I placed my trust, and unto Him is my recourse!" 30 If there were a Qur'an with which mountains were moved, or the earth were cloven asunder, or the dead were made to speak, (this would be the one!) But, truly, the command is with Allah in all things! Do not the Believers know, that, had Allah (so) willed, He could have guided all mankind (to the right)? But the Unbelievers,- never will disaster cease to seize them for their (ill) deeds, or to settle close to their homes, until the promise of Allah come to pass, for, verily, Allah will not fail in His promise. 31