(And judge between them by what Allah has revealed, and do not follow their inclinations)
This is a conjunction linked to "the Book." It is as if it were said: "And We have revealed to you the Book," and our statement: "And judge," refers to the command to judge—not the judgment itself—because what was revealed is the command to judge, not the judgment, and to avoid the nullification of the request entirely. You may also estimate the command to judge from the beginning of the matter without assuming the [elided] word "say," as investigated in al-Kashshaf.
It is permissible for it to be a conjunction linked to "the Truth" (al-haqq). Regarding its grammatical place, there are two views: the genitive and the accusative, based on the well-known disagreement. It is said: It is permissible for the sentence to be nominal, assuming an implicit subject, meaning: "And We have commanded: Judge..."
Some claim that "that" (an) is explanatory (tafsiriyyah), which Abu al-Baqa’ justified by estimating it as: "We commanded you," then explaining this command with "Judge." Abu Hayyan forbade correcting it this way, arguing that the deletion of the explained component by "that" (an) is not recorded in their [the Arabs'] language, and the matter is as he mentioned.
Al-Tayyibi said: If this speech were made a conjunction linked to "so judge" (fa-h-kum) in terms of meaning—so that the repetition is for the sake of attaching His statement, Exalted is He: (And beware of them, lest they tempt you away from some of what Allah has revealed to you)—it would be better. However, it was refuted by the fact that "that" (an) prevents that conjunction, and the matter of attachment is maintained in any case.
Some said: The command to judge was repeated because arbitration was sought from him (peace and blessings of Allah be upon him) twice: once regarding the adulterer who had previously been married, and once regarding a slain person between them; thus, each command arrived with the specific matter. This is reported from al-Jubba'i and Qadi Abu Ya'la.
The "nun" in "tempt you" (yaftinuka) allows for both damma and kasra. The clause formed by "that" (an) in "that they tempt you" acts as a substitute for the object pronoun—a substitute of inclusion—meaning: "And beware of their tempting you and turning you away from some of what Allah has revealed to you," even if it be the smallest amount, by depicting falsehood in the guise of truth.
Ibn Zayd said: [By turning you away] by lying about the Torah, claiming that this judgment is not in it. It is also permissible for it to be a verbal object (maf'ul li-ajlihi), meaning: "Beware of them out of fear that they might tempt you." The repetition of "what Allah has revealed to you" is for the sake of emphasizing the warning by highlighting the gravity of the affair. Perhaps this [repetition] is what cut off their greedy hopes—may Allah fight them.
Ibn Abi Hatim and al-Bayhaqi in al-Dala'il reported from Ibn Abbas (may Allah be pleased with them both) that the Jewish rabbis said: "Let us go to Muhammad (peace and blessings of Allah be upon him), perhaps we can tempt him away from his religion." They said: "O Muhammad, you know that we are the rabbis of the Jews, and if we follow you, the Jews will all follow us, and there is a dispute between us and our people, so let us take our dispute to you so you may judge for us against them, and we will believe in you and affirm you." The Messenger of Allah (peace and blessings of Allah be upon him) refused that, and then (If they turn away) was revealed—meaning: if they turn away from accepting the judgment by what Allah has revealed to you and desire something else—(then know that Allah only intends to afflict them with some of their sins).
This is a specific "some," and expressing it in this way is to signal that they have many sins; this, despite its extreme magnitude, is one among them. In this ambiguity lies an exaltation of the act of turning away, as in the verse: "He leaves places behind when I am not satisfied with them, or when some souls bind their death." He means by "some," himself—that is, a great soul, and "a soul" refers to the soul itself.
Al-Jubba'i said: "Some" is mentioned, but "all" is intended, just as the general is mentioned and the specific is intended. It is also said: The intent is an indefinite "some" to aggravate the punishment, as if to imply that it is enough to be seized for any of their sins—whichever it may be—and for them to be destroyed and annihilated by it.
Some claim that intending the "all" is not correct because the intent of this affliction is worldly punishment, which is specific to some sins and not others, whereas that which is general is the punishment of the Hereafter. According to what is reported from al-Hasan, this affliction refers to the expulsion of Banu al-Nadir. It is also said: The killing of Banu Qurayza. Others said: It is more general than that, including the expulsion of Banu Qaynuqa, the people of Khaybar, and Fadak, and this is perhaps the most likely view.
(And indeed, many of the people are defiantly disobedient), meaning: rebellious in disbelief, persisting in it, having exited the known boundaries. This is a follow-up, concluding objection that confirms the content of what preceded it, and it contains, for the Prophet (peace and blessings of Allah be upon him), a consolation that is self-evident.
It is also said: It is a conjunction linked to His saying, Exalted is He: "And We ordained for them therein," meaning: We ordained the law of qisas (retribution) in the Torah and confirmed it in the Gospel, and We revealed to you the Book confirming what is in them, "And indeed, many of the people are defiantly disobedient" regarding the divine laws established in the religions. Its remoteness is evident. "The people" here is intended in the general sense, though it is also said: The Jews.