Sanskrit
यथा प्रकाशयत्येकः कृत्स्नं लोकमिमं रविः । क्षेत्रं क्षेत्री तथा कृत्स्नं प्रकाशयति भारत ॥
yathā prakāśayaty ekaḥ kṛtsnaṃ lokam imaṃ raviḥ kṣetraṃ kṣetrī tathā kṛtsnaṃ prakāśayati bhārata
Translation
As the one sun illumineth the whole earth, so the Lord of the Field illumineth the whole Field, O Bhârata.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
A second simile, pairing with verse 33’s ether: as one sun illuminates the entire world, the Lord of the Field (kshetri — a name for purusha built directly off the kshetra/kshetrajna vocabulary that opened the chapter) illuminates the whole field. It returns to the light imagery verse 18 introduced (“the Light of all lights”) and gives it a concrete, visualizable form — consciousness as the single illuminating source behind all experience, rather than one light per experiencing body, echoing verse 3’s identification of the individual knower with the one cosmic Knower.