Surah Al-Kahf 18:86

His traveling and reaching the Place where the Sun sets (the West)

(So he followed a way.) Ibn `Abbas said that he followed different routes to achieve what he wanted.

(So he followed a way.) Mujahid said that he followed different routes, east and west. According to one report narrated from Mujahid, he said:

(a way) means, "A route through the land." Qatadah said, "It means he followed the routes and landmarks of the earth."

(Until, when he reached the setting place of the sun,) means, he followed a route until he reached the furthest point that could be reached in the direction of the sun's setting, which is the west of the earth. As for the idea of his reaching the place in the sky where the sun sets, this is something impossible, and the tales told by storytellers that he traveled so far to the west that the sun set behind him are not true at all. Most of these stories come from the myths of the People of the Book and the fabrications and lies of their heretics.

(he found it setting in a spring of Hami'ah) meaning, he saw the sun as if it were setting in the ocean. This is something which everyone who goes to the coast can see: it looks as if the sun is setting into the sea but in fact it never leaves its path in which it is fixed. Hami'ah is, according to one of the two views, derived from the word Hama'ah, which means mud. This is like the Ayah:

("I am going to create a man (Adam) from dried clay of altered Hama'h (mud)) 15:28, which means smooth mud, as we have discussed above.

(And he found near it a people.) meaning a nation. They mentioned that they were a great nation from among the sons of Adam.

(We (Allah) said (by inspiration): "O Dhul-Qarnayn! Either you punish them or treat them with kindness") means, Allah gave him power over them and gave him the choice: if he wanted to, he could kill the men and take the women and children captive, or if he wanted to, he could set them free, with or without a ransom. His justice and faith became apparent in the ruling he pronounced:

(As for him who does wrong,) meaning who persists in his Kufr and in associating others in worship with his Lord,

(we shall punish him,) Qatadah said, i.e., by killing him.

(and then he will be brought back unto his Lord, Who will punish him with a terrible torment.) meaning a severe, far-reaching and painful punishment. This implies a confirmation of the Hereafter and the reward and punishment.

(But as for him who believes), meaning `who follows us in our call to worship Allah Alone with no partner or associate,'

(he shall have the best reward,) meaning in the Hereafter, with Allah.

(and we (Dhul-Qarnayn) shall speak unto him mild words.) Mujahid said, `(words of) kindness.'

Ayat ini menjelaskan bahwa Zulkarnain menempuh jalan ke arah Barat. Setelah dia menempuh jalan itu, maka sampailah ia ke ujung bumi sebelah barat di mana kelihatan matahari terbenam seolah-olah masuk ke dalam lautan Atlantik. Di mana dia melihat matahari terbenam di dalam laut yang tampak kehitam-hitaman seperti lumpur. Dia telah melalui negeri Tunis dan Maroko dan sampailah ke pantai Afrika sebelah barat, dan di sana menjumpai beberapa kaum kafir. Allah telah menyuruhnya untuk memilih di antara dua hal, yaitu menyiksa mereka dengan pertumpahan darah atau mengajak mereka supaya beriman kepada Allah. Yang demikian ini dijelaskan dalam firman Allah yang disampaikan kepada Zulkarnain secara ilham. Zulkarnain disuruh supaya membunuh mereka jika mereka tidak mau mengakui Keesaan Allah dan tidak mau tunduk kepada ajakannya, atau mengajarkan kepada mereka petunjuk-petunjuk sehingga mereka mengenal hukum dan syariat agama dengan penuh keyakinan.