It is He who has made the earth submissive to you. Walk about in its land and eat of His provision. To Him is the Resurrection. 15 Are you so unafraid that He who is in Heaven will not open up the earth to swallow you, when it will begin to tremble? 16 Or do you feel secure that He who [holds authority] in the heaven would not send against you a storm of stones? Then you would know how [severe] was My warning. 17 And indeed those before them had denied – therefore how did My rejection turn out! 18 Do they not see the birds above them spreading and closing their wings? None save the Merciful sustains them. Surely, He observes all things. 19 Nay, who is there that can help you, (even as) an army, besides (Allah) Most Merciful? In nothing but delusion are the Unbelievers. 20 Or, who is it that shall provide for you if He withholds His provision? Yet they persist in arrogance and aversion. 21 What, is he who walks prone upon his face better guided than he who walks upright on a straight path? 22 Say: 'It is He who produced you, and appointed for you hearing and sight and hearts; little thanks you show!' 23 Say: 'It is He who scattered you in the earth, and unto Him you shall be mustered.' 24 But they [only] ask, "When is this promise to be fulfilled? [Answer this, O you who believe in it,] if you are men of truth!" 25 Say: The knowledge (thereof is only with Allah and I am only a plain warner. 26 When they see the torment approaching, the faces of the disbelievers will blacken and they will be told, "This is what you wanted to (experience)". 27 Say: "Just think: If God destroys me and those with me, or is benevolent to us, who will then protect the unbelievers from a painful doom?" 28 Say: 'He is the Merciful. In Him we believe and in Him we put all our trust. Indeed, you shall soon know who is in clear error' 29 Say [unto those who deny the truth]: "What do you think? If of a sudden all your water were to vanish underground, who [but God] could provide you with water from [new] unsullied springs?" 30