By whom, through effort, forms, rays, and light are perceived; He is the omniscient, the all-knower, whose manifestation is this within the body.

The knower (sarvajña, omniscient; sarvavit, all-knower) is identified as the principle by which all perception occurs. Yena (by whom) indicates instrument, not separate agent. It is the Ātman who enables perception, not the mind independently.

Rūpāṇi (forms), raśmīn (rays, resplendences), tejas (light, brilliance) — all these are objects of sensory perception. Yatnataḥ (through effort) indicates that even ordinary perception requires conscious energy, though we normally take it for granted. True yoga channels this effort toward self-inquiry.

The clause yasyaiṣaḥ antaḥ śarīre (whose manifestation is within the body) reiterates the internal location of the divine. It is not a remote god in heaven but the conscious presence animating every cell. The antaḥ (interiority) is key — everything we seek is within, not without.

The apparent paradox of “omniscient” in an individual body is resolved by understanding that the individual Ātman (jīvātman) is non-different from the universal Ātman (paramātman). Complete knowledge is revealed when identification with body-mind ceases. Then one sees that everything was always known, but ignorance hid it.