1 Gita Sloka Every Day - Chapter 13 - Kshetra Kshetrajna Yoga - Sloka 17

The entire content of this mail is from Swami Adidevananda's translation of Ramanuja's  Gita  Bhashya and Swami Chidbhavananda's Bhagavad Gita, both published by Ramakrishna Mission

One Appearing as the Many 16-17

1 Gita Sloka  Every Day - Chapter 13 - Kshetra Kshetrajna Yoga - Sloka 17

Jyotisham api tat jyotih tamasah param uchyate I

Gyanam gyeyam gyana gamyam hrudi sarvasya vishishtatham II sloka 17

ज्योतिषं अपि तत् ज्योतिः तामसाः परम् उच्यते I

ज्ञानम् ज्ञेयं ज्ञान गम्यम् हृदि सर्वस्य विशिश्तथम् II श्लोक 17 

The light of all lights, He is said to be beyond darkness; knowledge, the knowable, the goal of knowledge, seated in the hearts of all. 

Though the sun and the stars are self luminous, they lose their luminosity while in pralaya. Busshi acquires its powers of understanding from the Atman; but it also loses that borrowed faculty; whereas the Atman never loses its light. The physical light and darkness, characteristic of the inert matter, do not have any effect on or access to Atman. In pitch darkness, one is not able to see one's own body and clothing. But that darkness is no hindrance to the self-cognizing of its own presence. This self cognizance is not improved upon by the presence of sunlight. Self awareness is self evident. The sunlight and the darkness are perceived by the physical eye because of the light  it has acquired from the Atman enshrined in the heart. The senses perceive, the mind feels and the intellect cogitates because of the light they get from the Atman.