Tafsir of Ar-Rahman 55:41

(The criminals will be known by their marks): This is an independent clause serving the function of an explanation (ta‘lil) for the dismissal of the question.

As for (the criminals), it is said: The explicit noun is used in place of the pronoun to indicate that what is intended are some of the humans and some of the jinn—those who are criminals. Thus, it is like His saying, the Almighty: "The criminals will not be asked about their sins."

Their marks (simahum): According to what is narrated from al-Hasan, it is the blackening of the faces and the blueness of the eyes. Others said: It is the manifestation of gloom and sadness upon them. It is also permitted that they be other things, such as blindness, dumbness, and deafness. Hammad ibn Sulayman read it as bi-sima'ihim.

(Then they will be seized by the forelocks): Nawasi is the plural of nasiyah, which is the front part of the head.

(And the feet): Aqdam is the plural of qadam, which is the well-known foot of a person. The letter ba is for the instrument, similar to the ba in "I grabbed by the halter of the animal" (akhadhtu bi-khitam al-dabbah), and the prepositional phrase stands in the place of the subject (na'ib al-fa'il). Abu Hayyan said: The ba is for transitivity, and the verb implies the meaning of that which is transitive through it, meaning: "They shall be dragged by the forelocks, etc." There is debate regarding this.

The apparent view of more than one scholar is that the definite article al stands in place of the possessive pronoun, meaning: "By their forelocks and their feet." Abu Hayyan explicitly stated this, saying: The al in both is a substitute for the pronoun according to the school of the Kufans, while the pronoun is elided according to the school of the Basrans—that is, "by the forelocks and feet of them." You know that the disagreement between the two schools of the cities concerns when there is a need for a connecting pronoun, and there is no need for one here. Yes, the meaning is based upon the pronoun.

As for the manner of this seizing: It is narrated from al-Dahhak that the angel gathers the forelock of one of them and his two feet together in a chain behind his back, then breaks his back and casts him into the Fire. It is also said: The angels (peace be upon them) seize some of them by dragging them by the forelock, and others by dragging them by the feet. It is further said: The angels (peace be upon them) drag them at one time by seizing the forelocks and at another time by seizing the feet, in which case the wa (and) is in the sense of aw (or) for the purpose of classification, though this is contrary to the apparent meaning.

The agent (the angels) is left ambiguous because it is as if it were already determined. It is also said that it is to symbolize His magnificence. Ibn Marduyah and al-Diya' al-Maqdisi reported in Sifat al-Nar (The Description of the Fire) from Anas, who said: I heard the Messenger of Allah (may Allah bless him and grant him peace) say: "By Him in whose hand is my soul, the angels of Hell were created one thousand years before Hell itself was created. Every day, they increase in strength upon their strength, such that they shall seize whomever they seize by the forelocks and the feet."