۞ 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 Istawa (rose over) towards the heaven when it was smoke, and said to it and to the earth: "Come both of you willingly or unwillingly." They both said: "We come, willingly." 11 So He determined them as seven heavens in two days, and revealed its commandment in every heaven.' 12 Then if they Still turn away, say thou; I warn you of a calamity like the calamity of the 'Aad and Thamud. 13 When their apostles came to them from before them and from behind them, saying, Serve nothing but Allah, they said: If our Lord had pleased He would certainly have sent down angels, so we are surely unbelievers in that with which you are sent. 14 As for Aad, they behaved proudly in the earth without right. 'Who is stronger than us?' they would say. Could they not see that Allah, who created them, is stronger than they? But they disbelieved Our signs. 15 So We let loose on them a violent wind for several days of distress to make them taste a most disgraceful punishment here in this world, and far more shameful will be the punishment in the Hereafter, and there will be no succour for them. 16 As for Thamood, We guided them, but they preferred blindness above guidance, so the thunderbolt of the chastisement of humiliation seized them for that they were earning. 17 We only rescued the believers who had fear of God. 18