Tafsir of Az-Zukhruf 43:81

(Say) — i.e., to the disbelievers, to establish the truth and to alert them that your opposition to them in not worshipping what they worship of the angels—peace be upon them—is not due to hatred or enmity toward them or toward those they worship, but rather because of your certainty regarding the impossibility of what they have falsely attributed to them and upon which they have built their worship, namely that they are the daughters of Allah (the Exalted and Majestic)—(if the Most Gracious had a son, I would be the first of the worshippers).

The "if" refers to the existence of that son, and "kāna" (had) signifies validity, as one says, "It was not for you to do such and such," which is one of its usages. "Awwal" (first) is an elative noun (superlative), and the one to whom it is compared is the group addressed. It is permissible to consider this absolute, the intent being to manifest desire and promptness, though the first (interpretation) is what comes to mind.

The logic of the logical entailment is that he—peace and blessings be upon him—is the most knowledgeable of people regarding the affairs of the Exalted, what is permissible for Him, and what is not. He is the most keen to observe His rights and what they necessitate in terms of honoring His offspring—if He were to have any—since the right of a parent over a person necessitates that one honor the parent's child, as honoring the child is honoring the parent. Thus, the meaning is: If the Most Gracious had a son, and if that were valid and established by a sound proof that you could present and a clear argument that you could offer, then I would be the first to honor that son and the quickest of you to obey him and submit to him, just as a man honors the son of a king because of the greatness of his father. This is a negation of the existence of a son for Him—the Exalted—in the most eloquent manner. It is a demonstrative method and a dialectical theological approach; in reality, it is a hypothetical syllogism in which the negation of the consequent, the falsity of which is self-evident—namely, his—peace and blessings be upon him—worshipping a son—is used to prove the negation of the antecedent, namely the existence of a son for Him—the Exalted. This is similar to the Almighty’s saying: "Had there been therein gods besides Allah, both would have been ruined," except that here it is brought with "in" (if) rather than "law" (had), treating the content of the conditional as something whose non-existence is not decisively certain, by way of indulgence and slackening the reins for the sake of reproach and silencing.

In al-Kashf, it is stated that the verse is an exaggeration in that it makes the intrinsically possible—namely his—peace and blessings be upon him—worshipping what they claim to be a son—into something impossible. It is a negation of worshipping the son in the most eloquent way, by making it a result of an impossible premise, and then it is a negation of the son as well through another path: that since he—peace and blessings be upon him—did not worship the son, despite being the most deserving of worshipping him if he existed, it indicates his non-existence. This interpretation is mentioned in the verse as being narrated from Qatadah, al-Suddi, and al-Tabari.

'Abd al-Razzaq, 'Abd ibn Humayd, and Ibn Jarir narrated from Mujahid that the meaning is: Say, "If the Most Gracious had a son in your claim, then I am the first to worship Allah—the Exalted—alone, and I disbelieve in what you say." Thus, the intent of him—peace and blessings be upon him—being "the first of the worshippers" is that he is the first to deny that (claim) against them. The entailment in the conditional clause is that their attributing a son to Him—the Exalted—requires that the Prophet—peace and blessings be upon him—refute them and be the first to deny it, because he is the one tasked with the call to monotheism. This was hidden from the Imam (al-Razi), so he rejected the validity of this interpretation. Some struggled and said: The causal relationship of the consequence to the condition is based on the primacy in worship and monotheism among them; for when they unanimously agree upon that claim, the Prophet—peace and blessings be upon him—is inevitably the first among them in worshipping Allah—the Exalted—alone. It was also said: The causality is based on notification and mention, similar to "If you strike me, I will not strike you," which is better than the preceding. In truth, the connection is subtle and only appears to Mujahid.

Abu Hatim narrated from a group—without naming anyone—that "al-'abidin" is derived from "abada ya'badu," like "fariha yafrahu," meaning to feel disdain or aversion for something. From this is the saying: "And I feel disdain to satirize Kulayb through Darim," and the saying of another: "Whenever the loving friend wishes, he severs the tie," and he feels disdain for it inevitably, being an oppressor. That is: If the Most Gracious had a son, I would be the first of those feeling disdain for the son, or for the fact that he belongs to Allah—the Exalted—and for attributing him to Him—the Mighty and Majestic. A similar view is narrated from Ibn Abbas; al-Tha'labi narrated from him that Nafi' ibn al-Azraq said to him: "Tell me about the saying of the Almighty: 'I would be the first of the worshippers.'" He replied: "I am the first to feel aversion that Allah—the Exalted—should have a son." This is supported by the reading of al-Sulami and al-Yamani: "al-'abidin" (the averse), plural of "'abid" (averse), like "hadhir" (cautious) and "hadhirin" (cautious ones). This is the known meaning of "aversion," and it is rarely called "abid" (worshipper). Hence, Ibn 'Arafa weakened this view because of its use of a term rarely used in their speech. Al-Khalil mentioned in the book al-'Ayn that it was recited as "al-'abdin" with a quiescent 'ba', a lightened form of "al-'abidin" with a kasra. Abu Hatim said: "al-'abd" with a kasra on the 'ba' means intensely angry. Abu 'Ubaydah said: The Arabs say "abadani haqqi," meaning "my right was denied to me."

It is also narrated from al-Hasan, Ibn Zayd, and Zuhayr ibn Muhammad—and it is a narration from Ibn Abbas, Qatadah, and al-Suddi as well—that "in" is a negative particle: "The Most Gracious has not had a son, and I am the first to say that, and I have worshipped and professed unity." "Kana" here is for continuity, intended to signify the continuity of negation, not the negation of continuity. The "fa" (in "fa-ana") is for causality. This has been criticized as being contrary to the apparent meaning, with the aspect of causality being either hidden or forced. Makki claimed it is impermissible because it implies the negation of a son in the past, which is as you see.

Abdullah (ibn Mas'ud), Ibn Wathab, Talha, al-A'mash, Hamzah, and al-Kisa'i read—as the Qadi mentioned—"wuld" with a damma on the waw and a sukun on the lam, the plural of "walad" with fatha on both.