۞ 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 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 And He completed them as seven heavens within two days and inspired in each heaven its command. And We adorned the nearest heaven with lamps and as protection. That is the determination of the Exalted in Might, the Knowing. 12 But if they turn away, tell them: “I warn you against a sudden scourge like that which struck Ad and Thamud.” 13 Lo! There came unto them [God's] apostles, speaking of what lay open before them and what was [still] beyond their ken, [and calling unto them,] "Worship none but God!" They answered: "If our Sustainer had willed [us to believe in what you say,] He would have sent down angels [as His message-bearers]. As it is, behold, we deny that there is any truth in what you [claim to] have been sent with!" 14 Now the 'Ad behaved arrogantly through the land, against (all) truth and reason, and said: "Who is superior to us in strength?" What! did they not see that Allah, Who created them, was superior to them in strength? But they continued to reject Our Signs! 15 So We sent upon them a screaming wind during days of misfortune to make them taste the punishment of disgrace in the worldly life; but the punishment of the Hereafter is more disgracing, and they will not be helped. 16 We sent guidance to the people of Thamud but they preferred blindness to guidance so a humiliating blast of torment struck them for their evil deeds. 17 But We delivered those who believed and practised righteousness. 18