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 ye taken security from Him Who is in the heaven that He will not cause the earth to swallow you when lo! it is convulsed? 16 Do you feel secure that the One in the heavens will not strike you with a sandstorm? You will soon know, with the coming of the torment, how serious Our warning was. 17 And indeed those before them had denied – therefore how did My rejection turn out! 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 who is this that shall be a host for you to help you, apart from the All-merciful? The unbelievers are only in delusion. 20 Or is there any that could provide you with sustenance if He should withhold His provision [from you]? Nay, but they [who are bent on denying the truth] stubbornly persist in their disdain [of God's messages] and in their headlong flight [from Him]! 21 Is he who walks grovelling upon his face better guided, or he who walks upright upon 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 dispersed you all over the earth, and to Him you will be gathered." 24 They say, 'When shall this promise come to pass, if you speak truly?' 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 Say: "See ye?- If Allah were to destroy me, and those with me, or if He bestows His Mercy on us,- yet who can deliver the Unbelievers from a grievous Penalty?" 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 (O Muhammad SAW): "Tell me! If (all) your water were to be sunk away, who then can supply you with flowing (spring) water?" 30