(Muhammad), they will ask you about Dhu 'l-Qarnayn. Say, "I shall tell you something about him". 83 Verily We! We established him in the earth, and vouchsafed unto him of everything a way. 84 and he followed a way 85 Until when he reached the place where the sun set, he found it going down into a black sea, and found by it a people. We said: O Zulqarnain! either give them a chastisement or do them a benefit. 86 He said, 'As for the evildoer, him we shall chastise, then he shall be returned to his Lord and He shall chastise him with a horrible chastisement. 87 But as for him who believes and acts righteously, his will be a goodly reward and we shall enjoin upon him only mild commands." 88 Then he set out on another expedition 89 Until when he reached the rising place of the sun, he perceived it rising upon a nation for whom against it We had not set a veil. 90 Even so! and We had a full knowledge of what he had. 91 He then followed (another) road 92 [And he marched on] till, when he reached [a place] between the two mountain-barriers, he found beneath them a people who could scarcely understand a word [of his language]. 93 'ThulKarnain' they said, 'Look, Gog and Magog are corrupting the earth. Build for us a barrier between us and them, and we will pay you a tribute' 94 He answered: "That wherein my Sustainer has so securely established me is better [than anything that you could give me]; hence, do but help me with [your labour's] strength, [and] I shall erect a rampart between you and them! 95 Bring me ingots of iron." Then after he had filled up the space between the two mountain-sides, he said: "(Light a fire) and ply bellows." When he had made it (red like) fire, he said: "Bring me molten copper which I may pour on it." 96 And thus [the rampart was built, and] their enemies were unable to scale it, and neither were they able to pierce it. 97 He said: 'This is a mercy from my Lord. But when my Lord's promise is come, He will make it dust. The promise of my Lord is true' 98 ۞ And on that day we shall let some of them surge against others, and the Trumpet will be blown. Then We shall gather them together in one gathering. 99 On that Day We shall lay Hell bare before those who deny the truth, 100 who have turned a blind eye to My reminder and a deaf ear to My warning. 101