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 Do you feel secure that He who [holds authority] in the heaven would not cause the earth to swallow you and suddenly it would sway? 16 Do you feel secure that He who is in heaven will not loose against you a squall of pebbles, then you shall know how My warning is? 17 Those who have gone before you also belied (their Messengers) then how was My disapproval! 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 it that shall be your host to help you, other than the Merciful? Indeed, the unbelievers are only deluded. 20 Or who is this that shall provide for you if He withholds His provision? No, but they persist in disdain and aversion. 21 Who is better guided: he who walks grovelling on his face, or he who walks upright on a Straight Path? 22 Say thou: He it is who hath brought you forth and hath endowed you with hearing and sights and hearts. Little thanks it is ye give! 23 Say, "It is He who has multiplied you throughout the earth, and to Him you will be gathered." 24 And they say: When shall this threat be (executed) if you are truthful? 25 Say thou, [O Prophet:] "Knowledge thereof rests with God alone; and I am only a plain warner." 26 But when they see it drawing near, the faces of those who deny the truth will turn gloomy and they will be told, "This is what you were calling for." 27 Say: Have you considered if Allah should destroy me and those with me-- rather He will have mercy on us; yet who will protect the unbelievers from a painful punishment? 28 Say thou: He is the Compassionate; in Him we have believed, and in Him we have put our trust. And anon ye will know who it is that is in error manifest. 29 Say: 'What think you? If in the morning your water should have vanished into the earth, then who would bring you running water?' 30