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 whose hearts find comfort in the remembrance of God -- surely in the remembrance of God hearts can find comfort. 28 For those who believe and do good works is blessedness and blessed resort' 29 Thus have We sent you as a Messenger to a community before which many other communities have passed away that you may recite to them whatever We have revealed to you. And yet they deny the Lord of Mercy. Say to them: "He is my Lord, there is no god but Him. In Him I have placed all my trust and to Him I shall return." 30 And even if there were a Quran with which the mountains were made to pass away, or the earth were travelled over with it, or the dead were made to speak thereby; nay! the commandment is wholly Allah's, Have not yet those who believe known that if Allah please He would certainly guide all the people? And (as for) those who disbelieve, there will not cease to afflict them because of what they do a repelling calamity, or it will alight close by their abodes, until the promise of Allah comes about; surely Allah will not fail in (His) promise. 31