Tafsir of Ya seen 36:58

It is permissible for (Peace) to be a substitute (badal) for "what" (ma—in the previous verse: lahum ma yadda‘un), being a partial substitution (ba‘d min kull), and the requirement for a pronoun [linking the substitute to the substituted] is non-essential, provided it is not "Muslim" [in a literal sense].

His saying, the Exalted, (A word): This is an absolute object (maf‘ul mutlaq) for an omitted verb, and the sentence serves as an adjective (sifah) for "Peace."

His saying, the Exalted, (from a Merciful Lord): This is an adjective for "a word," meaning a peace that is spoken to them as a word from the side of a Merciful Lord—meaning He greets them from His side, the Exalted, without an intermediary, as an exaltation for them. Ibn Majah and a group [of scholars] recorded from Jabir, who said: The Prophet, peace be upon him, said: "While the people of Paradise are in their bliss, a light will shine upon them. They will raise their heads, and behold, the Lord will have appeared to them from above them and said: 'Peace be upon you, O people of Paradise.' This is the word of Allah, the Exalted: (Peace: A word from a Merciful Lord). He said: He will look at them and they will look at Him, and they will not turn their attention to any of the bliss as long as they are looking at Him, until He veils Himself from them, though His light and blessing remain upon them in their dwellings."

It has been said [that the greeting is] through the intermediary of the angels, peace be upon them, due to His saying, the Exalted: (And the angels will enter upon them from every gate, 'Peace be upon you'). This has been narrated from Ibn Abbas, and the majority favor the first [interpretation]. As for what has been said, that this is the angels' greeting to the believers at the time of death, it is of no weight. The aforementioned commencement is based on the premise that "what" (ma) is a general term.

It is also permissible for it to be an exhaustive substitution (badal kull min kull) on the assumption that a specific meaning is intended, or based on the claim of [the two being] equivalent for the sake of exaltation. There is no harm in substituting this indefinite noun for it if one considers it a relative noun (mawsul), for it is an indefinite noun described by the sentence that follows it. Furthermore, it is permissible to maintain the permissibility of substituting an indefinite noun for a definite one absolutely, without it being considered weak.

It is also permissible for (Peace) to be the predicate of an omitted subject, and the sentence following it is its adjective; meaning: "It—or that—is a peace that is spoken as a word from a Merciful Lord." The pronoun refers to "what," as does the demonstrative.

It is also permissible for it to be an adjective for "what," meaning: "They shall have what they call for, [being] safe or possessing peace from what they dislike." And (a word) is an infinitive (masdar) emphasizing His saying, the Exalted: (They shall have what they call for)—a peace, meaning a promise from a Merciful Lord. This adjectival interpretation holds if "what" is considered an indefinite noun described [by the following clause]; it is not valid if "what" is considered a relative noun due to the conflict between definiteness and indefiniteness.

It is also possible for it to be a predicate for "what," and (for them) is attached to it to indicate the source, as one says: "For Zayd, honor is abundant." Meaning: "What they call for is safe for them, pure, with no impurity in it." The accusative of (a word) is based on what you have heard just now.

In al-Kashshaf, the most likely of the aspects is that it is in the accusative for specialization (ikhtisas), which is one of his metaphorical interpretations. In that case, the statement is a sentence disconnected from what precedes it, and there is no pronoun involved in the accusative of the indefinite noun.

It is also permissible for it to be a subject whose predicate is omitted, meaning: "And for them is peace, which is spoken as a word from a Merciful Lord." The predicate was placed [as an introduction] so that the sentence would follow the style of its counterparts, not because it is prohibited to begin with an indefinite noun, for the indefinite noun is described by the sentence that follows it. The apparent meaning of their speech is the inclusion of a conjunction as well, though it is possible not to assume it, and the disconnection of the sentence is—as it is said—because it acts like a justification for what was contained in the verses before it; for the peace of the Merciful Lord is the origin of all exaltation and honoring.

On the assumption that it is a subject, it is permissible to assume the omitted predicate is "upon them." The Imam said: "It would then be an announcement from Allah, the Exalted, in the world, as if He—glorified be His Majesty—narrated to us, saying: (Indeed, the companions of Paradise are in an occupation), then when He completed the description of their state, He said: (Peace be upon them)." This is like His saying, the Exalted: (Peace be upon Nuh) and (Peace be upon the messengers). Thus, He—glorified and exalted be He—has shown favor to His believing servants just as He showed favor to His messengers. He then said: "This is an original and excellent interpretation that the text points toward." So we say: Or we say its implication is "Peace be upon you," and this is a type of transition (iltifat), as the Exalted said: "They have such and such," then He, the Exalted, said: (Peace be upon you).

The rationale for beginning with "Peace" in such a construction, whether it is described or not, is known to the students of knowledge. Muhammad ibn Ka'b al-Qurazi recited it as silm (with a kasra on the sin and a sukūn on the lam), and its meaning is "peace." Abu al-Fadl al-Razi said: "A state of reconciliation for them," meaning that is a state of reconciliation, but that is not the preferred view.

Ubayy, Abdullah, Isa, and al-Ghanawi recited it as (salaman) in the accusative as an infinitive, meaning: "He greets them with a peace," or as a state (hal) from the pronoun of "what" in the predicate, or from it based on the opinion of the permissibility of the state coming from the subject, meaning: "They shall have what they desire, [being] pure."