Tafsir of Al-Kahf 18:88

"As for he who believes" — that is, according to the requirements of my call — "and does righteous deeds" — according to what faith necessitates — "then for him" — in the two abodes — "is the reward of the best [deed]" — meaning, for him is the most excellent recompense, or the most excellent action, or Paradise. Jaza'an (reward) acts as an infinitive noun (masdar) confirming the content of the sentence; it is placed before the subject (mubtada') out of concern for it, or it is in the accusative case due to an implied verb (i.e., yujza biha jaza'an), and the sentence is either a circumstantial clause (hal) or an interjected clause between the subject and the predicate that precedes it, or it is a circumstantial qualifier itself (i.e., he is rewarded with it). Abu al-Hasan criticized this, stating that the Arabs hardly ever use the circumstantial qualifier in a preposed position except in poetry. Al-Farra' stated: It is in the accusative case as a specifier (tamyiz).

Ibn Abbas and Masruq recited it as jaza'u in the accusative case without tanwin. Al-Mahdawi explained this as the omission of tanwin to avoid two quiescent consonants meeting, while others explained it as an omission due to the genitive construction (idafa), with the subject being implied because the meaning points to it, i.e., "for him is the reward, the reward of the best deed."

Abdullah ibn Abi Ishaq recited it in the nominative case with tanwin, interpreting it as the subject, while al-husna is its substitute (badal), and the predicate is the prepositional phrase. More than one of the seven reciters recited it in the nominative case without tanwin, explained as a subject in a genitive construction. Abu Ali said: The meaning, based on the genitive construction, is "the reward of the good deeds which he performed and did," or the meaning of al-husna is Paradise, with the genitive construction similar to "the abode of the Hereafter" (dar al-akhirah).

"And we shall speak to him of our command" — meaning, from what we command — "with ease" — meaning, something easy, facilitated, and not burdensome. The implied meaning is "that which possesses ease," and the infinitive noun is applied to it as an exaggeration. Abu Ja'far recited yusran (with two dammahs) wherever it occurs. At-Tabari said: The intent regarding the taking of captives is to show kindness; thus, he was given the choice between killing and taking captive. The meaning is: either you punish by killing, or you show kindness to them by sparing their lives and taking them captive. The response narrated regarding this is said to be of the "wise style," for the apparent meaning is that Allah, Exalted is He, gave him the choice regarding killing or capturing them while they were disbelievers. Thus, he said: As for the disbeliever, one observes the strength of Islam regarding him, and as for the believer, he is not subjected to anything except what is mandatory.

In al-Kashf, it is mentioned that in both aspects, a nuance was observed by mentioning what is from Allah, Exalted is He, regarding mercy, indicating that what comes from Him is secondary and a completion. Regarding the side of punishment, it observes the order of existence alongside gradation, so that it may be more infuriating. It is as if he interpreted "then for him" based on the meaning of "for him from Allah, Exalted is He," which is the apparent meaning. He also permitted interpreting "either you punish or you take" as a distribution rather than a choice. The meaning, according to what has been said, is: Let your state with them be either punishment or kindness; the former for those who remain in their state, and the latter for those who repent. So reflect upon this.