jyotiḥ

अग्निर्ज्योतिरहः शुक्लः षण्मासा उत्तरायणम्

jyotiḥ — light

Fire, light, day, the bright fortnight, the six months of the sun's northern course: departing then, those who know Brahman go to Brahman.

धूमो रात्रिस्तथा कृष्णः षण्मासा दक्षिणायनम्

jyotiḥ — light

Smoke, night, the dark fortnight, the six months of the southern course: departing then, one reaches the light of the moon and returns.

ज्योतिषामपि तज्ज्योतिस्तमसः परमुच्यते

jyotiṣhām — in all luminarie

The light of lights, said to be beyond the dark; it is knowledge, what is to be known, and what knowledge reaches — seated in the heart of all.