تَصْلَىٰ نَارًا حَامِيَةً
Root: ص-ل-ي. To be thrown into fire, to be roasted in fire, to remain within the flame. From the same root ṣilā (entering the fire), taṣliya, and muṣlā (a place of roasting).
The concrete side of the root matters: ṣala'l-laḥma — he roasted the meat over the fire. That is, the verb recounts not an approaching to the fire but the fire's working upon a thing.
Its uses in the Qurʾān confirm this: "He will soon enter a flaming fire" (al-Masad 111/3); "I shall cast him into Saqar" (al-Muddaththir 74/26).
A variant reading. The verb has been read both taṣlā (active: it enters) and tuṣlā (passive: it is made to enter). The difference is meaningful but small: in the first the subject is the faces, in the second there is an agent and it is not stated. I do not give the names of the imams of the variant readings; the existence of the difference is certain, its distribution I cannot give with certainty.
One observation: the active reading accords with the general logic of the sūra. Those faces have been described from the beginning as possessing agency — they work, they grow weary. They enter the fire themselves too. The chain of acts is not broken; only none of it is of any use.
Root: ح-م-ي. To grow hot, to become heated, to be made red-hot. Ḥamiya'l-ḥadīd — the iron grew red-hot.
- The heat branch: ḥamy, ḥāmī (blazing), ḥummā (high fever, the illness of fever).
- The protection branch: ḥimā (a protected pasture, an inviolable ground), ḥimāya, ḥāmī (one who protects).
The two branches come from the same three letters and the lexicographers look for a unity of original sense between them; but I do not force this link. The word in the verse belongs beyond dispute to the first branch: a fire made red-hot.
The function of the attribute. Fire is hot in any case; to say "blazing fire" may look like a repetition. But the pattern ḥāmiya conveys the last degree of heat — the state turned red, arrived at its peak. The same logic will be repeated one verse later for water: the spring too will not be ordinary but arrived at boiling point.