Tafsir of An-Nahl 16:29

"Abiding eternally therein" — this is a prospective state (ḥāl muqaddara) if the "entry" is intended to mean the occurrence of the act, or a simultaneous state if "absolute existence" is intended. As for the pronoun in "therein," it is said to refer to the "gates" in the sense of layers, and it is said to refer to "Hell." The latter is preferred, and treating the state as prospective is considered less plausible. Interpreting "eternity" (khulūd) as "long-staying" is done to avoid this necessity, although such an interpretation occurs in their discourse contrary to what is customary in the Noble Quran.

"So evil is the residence of the arrogant" That is, [arrogant] toward monotheism. They are mentioned by the title of "arrogance" (takabbur) to intimate its status as the cause of their requital therein. The Almighty had previously described the disbelievers as having "sought arrogance" (istikbār), and here as having "arrogance" (takabbur). Al-Rāghib mentions that these terms and "pride" (kibr) are close in meaning. "Pride" is a state specific to a person due to their self-admiration. "Seeking arrogance" (istikbār) is of two types: first, that a person strives and seeks to become great—this is when he loves it, in the place he loves, and at the time he loves, and this is praiseworthy. Second, that he feigns greatness, displaying that which he does not possess, and this is blameworthy. "Arrogance" (takabbur) is also of two types: first, that one’s good actions are many in reality, and superior to the merits of others; in this sense, Allah Almighty is described as "The Proud" (al-Mutakabbir). Second, that one is affected and feigns greatness, which is the description of the general populace. Arrogance of the first type is praiseworthy, while the second is blameworthy.

The subject of the dispraise is omitted; that is, "Hell" or "its gates," if interpreted as levels. The fa is for conjunction, and the lām is brought for emphasis, out of concern for the dispraise, because these people were misguided and misguiding, as indicated by the Almighty’s saying: "That they may bear their burdens in full on the Day of Resurrection, and some of the burdens of those whom they misguide without knowledge." Similarly, for the sake of emphasis, the lām is also brought for praise in the subsequent saying of the Almighty: "And the home of the Hereafter is best, and most excellent is the home of the righteous," because those people [the righteous] are the opposite of these—they are guides and guided. It is as if, due to the absence of this necessity in the verses of Surah Az-Zumar and Surah Ghafir (The Believer), the lām was not brought there. It is said: "So evil is the residence of the arrogant." It is also said that the emphasis is directed toward what is understood from the sentence—that Hell is their residence. Since this was not understood from the verses prior to this point—as it was understood before those two verses in those two Surahs—the emphasis was brought there and not here, sufficing with what is almost explicit in conveying that it is their residence, which you will hear [discussed], God willing, there.