Tafsir of Al-Kahf 18:34

And he had—meaning, for the aforementioned individual, the owner of the two gardens—thamar (various types of wealth), as in al-Qamus and other lexicons. It is said: "He thamara," meaning he acquired wealth. Interpreting it as the fruit of trees, as Abu Hayyan and others have done, is not appropriate for the structure of the discourse.

Ibn Abbas, Mujahid, Ibn Amir, Hamzah, al-Kisa'i, Ibn Kathir, Nafi', and the reciters of Medina recited it as thumur (with a damma on the tha' and the mim). This is likewise the case for bi-thumurihi (in its fruit) appearing later, for it is the plural of thimar (with a kasra on the tha'), which is the plural of thamar (with two fathas); thus, it is the plural of the plural. Its meaning—as previously established—is: abundant wealth of gold, silver, livestock, and other things. Ibn Abbas, Qatadah, and others interpreted it in this manner. Mujahid said that it refers specifically to gold and silver. Al-A'mash, Abu Raja', and Abu 'Amr recited it with a damma on the tha' and a sukun on the mim as a simplification, both here and subsequently, and the meaning remains as you have heard. In one narration, Abu Raja' also recited it as thamr (with a fatha on the tha' and sukun on the mim).

In the codex of Ubayy, it is rendered as an interpretation: "And We gave him abundant wealth."

And he said to his companion—the believer. The intent behind "companion" is the linguistic meaning, so this designation does not contradict the statement that they were brothers, contrary to those who were mistaken. While he was arguing with him—that is, arguing with his companion. The sentence is in the position of a state (hal) of the speaker. Muhiwarah (arguing) is the exchange of speech, derived from hara (he returned), meaning he was returning speech to him in his denial of the Resurrection and his associating partners with Allah, Exalted and Majestic. It is permissible that the sentence is in the position of a state of his companion, in which case the pronoun "he" refers to him, and the pronoun in "his companion" refers to the speaker; that is, the believing companion was responding with exhortation and calling to Allah, Exalted and Majestic, to that disbeliever.

I am greater than you in wealth and mightier in retinue—meaning, in servants and helpers. It is said: male children. This is narrated from Qatadah and Muqatil, and it is supported by the counter-statement, "less than you in wealth and children." Male children are specified because they are the ones who set forth (yanfiru) with him for his interests and assistance. Others said it means "clan," as it is the nature of a clan to set forth with those who belong to them. This has been used as proof that he was not his brother, for the clan is shared between them, and one who maintains brotherhood does not explain it in such a way.

The nouns malan (wealth) and nafran (retinue) are in the accusative case as specifications (tamyiz). According to some, it is transformed from an initial subject (mubtada'). It is apparent that the intent of the comparative form (af'al at-tafdil) is its literal meaning. In this case, it refutes the content of some narrations which suggest that the believing brother remained poor and needy after giving away his wealth in charity, so he asked his disbelieving brother for help, who refused him and scolded him for giving charity.