SB 3.30.20
yatana-deha avrtya
pasair baddhva gale balat
nayato dirgham adhvanam
dandyam raja-bhata yatha
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As a criminal is arrested for punishment by the constables of the state, a person engaged in criminal sense gratification is similarly arrested by the Yamadutas, who bind him by the neck with strong rope and cover his subtle body so that he may undergo severe punishment.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Every living entity is covered by a subtle and gross body. The subtle body is the covering of mind, ego, intelligence and consciousness. It is said in the scriptures that the constables of Yamaraja cover the subtle body of the culprit and take him to the abode of Yamaraja to be punished in a way that he is able to tolerate. He does not die from this punishment because if he died, then who would suffer the punishment? It is not the business of the constables of Yamaraja to put one to death. In fact, it is not possible to kill a living entity because factually he is eternal; he simply has to suffer the consequences of his activities of sense gratification.
The process of punishment is explained in the Caitanya-caritamrta. Formerly the king’s men would take a criminal in a boat in the middle of the river. They would dunk him by grasping a bunch of his hair and thrusting him completely underwater, and when he was almost suffocated, the king’s constables would take him out of the water and allow him to breathe for some time, and then they would again dunk him in the water to suffocate. This sort of punishment is inflicted upon the forgotten soul by Yamaraja, as will be described in the following verses.