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 Those who believe, their hearts being at rest in God's remembrance -- in God's remembrance are at rest the hearts 28 The righteously striving believers will receive abundant blessings and the best eternal dwelling. 29 Thus have We sent you to a community before which [other] communities have passed on so you might recite to them that which We revealed to you, while they disbelieve in the Most Merciful. Say, "He is my Lord; there is no deity except Him. Upon Him I rely, and to Him is my return." 30 If only a Koran whereby the mountains were set in motion, or the earth cleaved asunder, or the dead spoken to. No, but to Allah is the affair altogether. Do those who believe know that had Allah willed He could have guided all people? As for those who disbelieve, because of what they do, disaster will not cease to afflict them, or it alights near their home until the promise of Allah comes. Allah will not break His promise. 31