Sbg 13.18 ecsiva
English Commentary By Swami Sivananda 13.18 ज्योतिषाम् of lights, अपि even, तत् That, ज्योतिः Light, तमसः from darkness, परम् beyond, उच्यते is said (to be), ज्ञानम् knowledge, ज्ञेयम् that which is to be known, ज्ञानगम्यम् attainable by knowledge, हृदि in the heart, सर्वस्य of all, विष्ठितम् seated.