"Whenever their skins are cooked through, We shall replace them with other skins"

Yahya said: It reached us that it [the Fire] consumes everything until it reaches the heart. The heart then cries out, and Allah does not wish for it to consume their hearts. When it finds nothing left of them to cling to, it subsides—meaning: it calms down—then they are recreated as a new creation, and it consumes them whenever they are recreated.