Those who have rejected (the message of Muhammad) say: "Why has no sign been sent down upon him from his Lord?" Tell them: "Allah lets go astray those whom He wills, and guides to Himself those who turn to Him." 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 For those who believe and do good works is blessedness and blessed resort' 29 Thus We send thee (O Muhammad) unto a nation, before whom other nations have passed away, that thou mayst recite unto them that which We have inspired in thee, while they are disbelievers in the Beneficent. Say: He is my Lord; there is no Allah save Him. In Him do I put my trust and unto Him is my recourse. 30 And what would have happened were a Qur'an to be revealed wherewith mountains could be set in motion, or the earth cleft, or the dead made to speak? (To show such signs is not at all difficult for) everything rests entirely with Allah. So, do not the people of faith (still look forward to such a sign in response to the demand of the unbelievers and) despair as a result of knowing that had Allah so willed, He could have guided all to the Truth. Misfortune continues to afflict the unbelievers on account of their misdeeds, or to befall on locations close to their habitation. This will continue until Allah's promise (of chastisement) is fulfilled. Indeed Allah does not go back upon His promise. 31