The expansion of ignorance is explained in this verse. The first ignorance is to identify one’s material body, which is made of five elements, as the self, and the second is to accept something as one’s own due to a bodily connection. In this way, ignorance expands. The living entity is eternal, but because of his accepting nonpermanent things, misidentifying his interest, he is put into ignorance, and therefore he suffers material pangs.