COMMENTARY on 4:56
Muhammad Asad:

Translation:
for, verily, those who are bent on denying the truth of Our messages We shall, in time, cause to endure fire: [and] every time their skins are burnt off, We shall replace them with new skins, so that they may taste suffering [in full] 73 Verily, God is almighty, wise.
Commentary:
73  This awesome allegory of suffering in the life to come is obviously meant to bring out the long-lasting nature of that suffering (Razi).