۞ Say: What! do you indeed disbelieve in Him Who created the earth in two periods, and do you set up equals with Him? That 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 directed Himself to the heaven and it is a vapor, so He said to it and to the earth: Come both, willingly or unwillingly. They both said: We come willingly. 11 And He [it is who] decreed that they become seven heavens in two aeons, and imparted unto each heaven its function. And We adorned the skies nearest to the earth with lights, and made them secure: such is the ordaining of the Almighty, the All-Knowing. 12 Then if they Still turn away, say thou; I warn you of a calamity like the calamity of the 'Aad and Thamud. 13 [That occurred] when the messengers had come to them before them and after them, [saying], "Worship not except Allah." They said, "If our Lord had willed, He would have sent down the angels, so indeed we, in that with which you have been sent, are disbelievers." 14 Then as to Ad, they were unjustly proud in the land, and they said: Who is mightier in strength than we? Did they not see that Allah Who created them was mightier than they in strength, and they denied Our communications? 15 Then We loosed against them a wind clamorous in days of ill fortune, that We might let them taste the chastisement of degradation in the present life; and the chastisement of the world to come is even more degrading, and they shall not be helped. 16 And as for Thamud, We guided them, but they preferred blindness over guidance, so the thunderbolt of humiliating punishment seized them for what they used to earn. 17 But We delivered those who believed and practised righteousness. 18