It is He Who has made the earth manageable for you, so traverse ye through its tracts and enjoy of the Sustenance which He furnishes: but unto Him is the Resurrection. 15 Have you become unafraid of the One Who controls the heavens, that He will not cause you to sink into the earth when it trembles? 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 Those who came before them also gave the lie (to the Messengers): then how awesome was My chastisement! 18 Have they not seen the birds above them spreading out their wings and closing them? Naught upholdeth them save the Beneficent. Lo! He is Seer of all things. 19 Or which army do you have that will help you against the Most Gracious? The disbelievers are in nothing except an illusion. 20 Who can provide for you, if He withholds His provision? Yet they obstinately persist in rebellion and avoidance of the truth. 21 Who is better guided: he who walks grovelling on his face, or 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 God who has settled you on the earth and to Him you will be resurrected". 24 And they say, "When is this promise, if you should be truthful?" 25 Say thou, [O Prophet:] "Knowledge thereof rests with God alone; and I am only a plain warner." 26 When they realise it has come upon them, distraught will be the faces of unbelievers. They will be told: "This is what you asked for." 27 (Muhammad), say, "Have you not considered that regardless whether God forgives me and my followers or grants us mercy, but who will protect the disbelievers from a painful torment? 28 Say, "He is the Most Gracious: we believe in Him and we put our trust in Him. You will soon come to know who is in evident 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