Those who disbelieve say: If only a portent were sent down upon him from his Lord! Say: Lo! Allah sendeth whom He will astray, and guideth unto Himself all who turn (unto Him), 27 Those who have believed and whose hearts are assured by the remembrance of Allah. Unquestionably, by the remembrance of Allah hearts are assured." 28 For those who believe and do good works is blessedness and blessed resort' 29 That is how We have sent you to a people before whom many a people have come and gone, so that you may announce to them whatever We have revealed to you. But they do not believe in Ar-Rahman. Tell them: "He is my Lord. There is no other god but He. In Him have I placed my trust, and to Him is my reversion." 30 Yet even if [they should listen to] a [divine] discourse by which mountains could be moved, or the earth cleft asunder, or the dead made to speak - [they who are bent on denying the truth would still refuse to believe in it]! Nay, but God alone has the power to decide what shall be. Have, then, they who have attained to faith not yet come to know that, had God so willed; He would indeed have guided all mankind aright? But as for those who are bent on denying the truth - in result of their [evil] deeds, sudden calamities will always befall them or will alight close to their homes; [and this will continue] until God's promise [of resurrection] is fulfilled: verily, God never fails to fulfil His promise! 31