They ask you about Dhu'l-Qarnain. 83 We established him in the land, and We gave him a way to everything; 84 So he followed a way 85 until when he reached the very limits where the sun sets, he saw it setting in dark turbid waters; and nearby he met a people. We said: "O Dhu al-Qarnayn, you have the power to punish or to treat them with kindness." 86 He replied, "I shall punish the unjust ones among them and then they will return to their Lord, who will punish them more sternly". 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 And once again he chose the right means [to achieve a right end]. 89 To the extent that when he reached the rising-place of the sun, he found it rising upon a nation for which We had not kept any shelter from it. 90 This indeed was true. We knew all that he did there. 91 Then he followed a way 92 until he came between two mountains. He found beside 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 replied: 'That which my Lord has given me is better, therefore help me with all your power, and I will build a barrier between you and between them. 95 bring me blocks of iron." Then, when he had filled the gap between the mountain sides [he said], "Now blow on the fire with your bellows." When the iron blocks were red with heat, he said, "Bring me molten brass to pour on them." 96 So Gog and Magog were unable to pass over it, nor were they able [to effect] in it any penetration. 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 ۞ Upon that day We shall leave them surging on one another, and the Trumpet shall be blown, and We shall gather them together, 99 And We will bring forth hell, exposed to view, on that day before the unbelievers. 100 whose eyes had been veiled against Our Quran and who were not able to hear (its recitation). 101