यद्भासा भास्यतेऽर्कादि भास्यैर्यत्तु न भास्यते ।येन सर्वमिदं भाति तद्ब्रह्मेत्यवधारयेत् ॥ ६१ ॥
In plain words
The sun and every other light shine because its light falls on them; nothing they light can ever light it. Everything here shines only by it. Settle it firmly: that is Brahman.
Close to the Sanskrit
That by whose light the sun and the rest are illumined, but which is not illumined by those illumined things; that by which all this shines — that one should ascertain as Brahman.