The quality of a lighted body is colour. That is apprehended by the eye. Aditya who always lives in the eye has been appointed in the perception of colour.
ज्योतिषश्च गुणो रूपं चक्षुषा तच्च गृह्यते। चक्षुःस्थश्च सदाऽऽदित्यो रूपज्ञाने विधीयते।।३शा