Tafsir of Al-Mu'minoon 23:104

His saying—the Exalted—"The Fire will scorch their faces" is a circumstantial clause or an inaugural sentence. Al-Lafh (scorching) is the touch of the Fire’s flame upon a thing. It is, as al-Zajjaj said, more intense in its effect than al-Nafh (a puff). The intended meaning is: the Fire will burn their faces. The specification of the faces in this regard is because they are the most noble of the limbs; thus, clarifying their state is a greater deterrent against the sins that lead to the Fire. This is the secret behind placing the object before the agent.

"And they therein will be Kalihun (grimacing/distorted)."

They are those whose lips are shriveled away from their teeth as a result of that scorching. It has been authentically reported in the narration of al-Tirmidhi and a group [of scholars] from Abu Sa’id al-Khudri—may Allah be pleased with him—from the Messenger of Allah—may Allah bless him and grant him peace—that he said regarding this verse: "The Fire distorts them, so the upper lip shrivels until it reaches the middle of the head, and the lower lip hangs down until it strikes the navel." Ibn Marduyah and al-Diya’ recorded in [the description of the Fire] from Abu al-Darda’, who said: The Messenger of Allah—may Allah bless him and grant him peace—said regarding His saying—the Exalted—"will scorch..." etc.: "It will scorch them with a scorching, such that their flesh will melt down onto their heels." From Ibn ‘Abbas—may Allah be pleased with both of them—it is narrated that al-Kuluh is the tightening and contracting of the face. Abu Haywah, Abu Bahriyyah, and Ibn Abi ‘Ablah read it as Kaliḥūn without an alif, being the plural of Kaliḥ, like Ḥadhir.