Thou hast in thee a supreme soul, better than this soul and beyond the perception of all subtile elements and which cannot be conceived. Glory be to that Purusottam form of thine. And salutation be to that imperishable form of thine, O lord of gods, which is the soul of all creatures, another manifestation of thy might and which is the refuge of all qualities.

In plain words: Prahlada praises an even higher Supreme Soul in Vishnu. It lies beyond the individual soul and cannot be sensed or imagined. He bows to this highest form, called Purushottama (the Supreme Person), the soul of all creatures.