۞ Say: 'Do you disbelieve in Him who created the earth in two days? And do you set up equals with Him? He is the Lord of the Worlds' 9 He placed therein (i.e. the earth) firm mountains from above it, and He blessed it, and measured therein its sustenance (for its dwellers) in four Days equal (i.e. all these four 'days' were equal in the length of time), for all those who ask (about its creation). 10 Then He turned to heaven when it was vapour and said to it and to the earth, "Come willingly or unwillingly." They both said, "We come willingly," 11 Then He created several skies in two spans, and ingrained in each sky its function, decking the nearest heaven with lamps, and guarded it. This has been determined by the mighty and all-knowing. 12 If they turn away, then say, "I warn you of a lightning-bolt like the one which struck the 'Ad and the Thamud: 13 When the Messengers (of Allah) came to them from the front and from the rear, saying: “Do not serve any but Allah”; they said: “Had our Lord so willed, He would have sent down angels. So we deny the Message you have brought.” 14 Now as for [the tribe of] Ad, they walked arrogantly on earth, [offending] against all right, and saying, "Who could have a power greater than ours?" Why - were they, then, not aware that God, who created them, had a power greater than theirs? But they went on rejecting Our messages; 15 whereupon We sent upon them a fierce wind on inauspicious days that We might make them taste a degrading chastisement in the life of this world. And surely the chastisement of the Hereafter is even more degrading. There will be none to help them there. 16 As for the (tribe of) Thamud, We tried to guide them, but they preferred blindness to guidance; then they were seized by the torment of a humiliating punishment as requital for their misdeeds; 17 And We delivered those who believed and used to keep their duty to Allah. 18