(And they ask you) O Muhammad ,
(about Dhul-Qarnayn.) i.e., about his story. We have already mentioned how the disbelievers of Makkah sent word to the People of the Book and asked them for some information with which they could test the Prophet . They (the People of the Book) said, `Ask him about a man who traveled extensively throughout the earth, and about some young men who nobody knows what they did, and about the Ruh (the soul),' then Surat Al-Kahf was revealed. Dhul-Qarnayn had great Power
(Verily, We established him in the earth,) means, `We have given him great power, so that he had all that kings could have of might, armies, war equipment and siege machinery.' So he had dominion over the east and the west, all countries and their kings submitted to him, and all the nations, Arab and non-Arab, served him. Some of them said he was called Dhul-Qarnayn (the one with two horns) because he reached the two "Horns" of the sun, east and west, where it rises and where it sets.
(and We gave him the means of everything.) Ibn `Abbas, Mujahid, Sa`id bin Jubayr, `Ikrimah, As-Suddi, Qatadah, Ad-Dahhak and others said, "This means knowledge." Qatadah also said,
(and We gave him the means of everything.) "The different parts and features of the earth." Concerning Bilqis, Allah said,
(she has been given all things) 27:23, meaning all things that monarchs like her are given. Thus too was Dhul-Qarnayn: Allah gave him the means of all things, meaning the means and power to conquer all areas, regions and countries, to defeat enemies, suppress the kings of the earth and humiliate the people of Shirk. He was given all that a man like him would need. And Allah knows best.