Tafsir of Ghafir 40:83

(Then when their messengers came to them with clear proofs)—meaning miracles or manifest signs that encompass what is necessary—(they rejoiced in what they had of knowledge). Six interpretations have been mentioned regarding this:

The first: That "knowledge" refers to their deviant creeds, their fallacious misconceptions regarding the origin, the resurrection, and other matters; or their doctrines concerning the states of the Afterlife, as is the apparent position of al-Kashshaf. Expressing this as "knowledge" according to their own claim is a form of mockery, as in the words of the Almighty: "...but their knowledge is confused about the Hereafter" (27:66). The meaning is that they rejoiced in this [false knowledge], disparaged the knowledge of the Messengers (peace be upon them) because of it, and used it to repel the clear proofs.

The second: That it refers to the knowledge of philosophers and materialists among the Greeks, in its various forms. When they heard of the revelation of God the Almighty, they rejected it and belittled the knowledge of the Prophets (peace be upon them) in comparison to what they possessed of that [philosophy]. It is narrated that Socrates heard of Moses (peace be upon him) and was told, "If only you would emigrate to him!" He replied, "We are a refined people, and we have no need of someone to refine us." Time repeats itself, for we have seen those who abandoned following the Seal of Messengers (may God bless him and grant him peace) and disdained being attributed to the law of any of them, rejoicing in the scraps they licked from the philosophers, saying, "Knowledge is that, not what the Messengers—may the blessings and peace of God be upon them all—brought."

The third: That the underlying meaning is: "When their messengers came to them with clear proofs, they did not rejoice in the knowledge that came to them." Thus, they replaced it: they rejoiced in what they had of "ignorance." Then, this ignorance was termed "knowledge" because of their attachment to it and their placing it in the position where they should have instead been attached to the knowledge that had come to them. This contains mockery of the extent of their ignorance and exaggeration in their lack of [true] knowledge. In this interpretation, the pronouns in "rejoiced" and "had" refer to the disbelievers about whom the account is given.

The fourth: That the pronoun in "rejoiced" is assigned to the disbelievers, and the pronoun in "had" is assigned to the Messengers (peace be upon them). "Knowledge" here refers to the truth that the Messengers brought—meaning, they rejoiced in the knowledge the Messengers possessed with a laughter of derision and mockery. In summary, they mocked the clear proofs and the knowledge of revelation brought by the Messengers. This is supported by the Almighty’s words: "...and they will be enveloped by what they used to mock."

The fifth: That both pronouns are assigned to the Messengers (peace be upon them). The meaning is that when the Messengers saw the persistent ignorance of the disbelievers and their mockery of the truth, and knew the evil of their end and the punishment that would befall them for their ignorance and mockery, they rejoiced in the knowledge they had been given and thanked God the Almighty, while the penalty for their ignorance and mockery enveloped the disbelievers. This is reported on the authority of al-Jubba'i.

The sixth: That both pronouns are assigned to the disbelievers, and "what they had of knowledge" refers to their knowledge of worldly affairs and their expertise in managing them, as the Almighty says: "...they know but the outer appearance of the worldly life, and they are, of the Hereafter, unaware. That is the extent of their knowledge." (30:7). Thus, when the Messengers came to them with the knowledge of religion—which is the thing furthest from their own knowledge because it demands the abandonment of the world and restraint from delights and lusts—they paid no attention to it, belittled it, mocked it, and believed that there was no knowledge more beneficial or more likely to bring advantages than their own. Thus, they rejoiced in it.

The author of al-Kashf said: "The most likely of these six views is the third. It contains mockery, an exaggeration of their void of knowledge, and includes what the first view includes while being free from the failure to correspond to reality, as seen in the second view, and free from the inadequacy of expression as in the fourth, and free from the disruption of pronouns as in the fifth. The sixth is similar, but it lacks the benefits of the third." Thus, contemplate this deeply.

Abu Hayyan favored the sixth view and challenged the third, arguing that an affirmative sentence is not used to express a negative one except in rare cases—such as the proverb "A dog barking is worse than a biting one," though even that is contested—and that when the matter ultimately becomes an affirmation of something prohibited, it is permissible. As for the verse, it should not be burdened with the rare, for that would lead to a confusion of the distinct meanings of sentences, leaving none of them trustworthy. You, however, know that there is no contradiction in meaning between "they did not rejoice in the knowledge that came to them" and "they rejoiced in what they had of knowledge" according to what we have established. Indeed, while this view has merit in my opinion, it is not without remoteness, and the words of the author of al-Kashf are not without being subject to scrutiny.