In the beginning the earth was without form and void and DARKNESS was upon the face of the deep. And Ruach Elohiym moved upon the face of the waters. And Elohiym said: Let there be LIGHT, and there was Light -- Bere'shiyth (Genesis) 1: 3-2.
Only on the 3rd day after LIGHT was created -- in verse 14: And Elohiym said: Let there be lights in the expanse of the heavens to divide day from night. in verse 16: And Elohiym made 2 great lights, the greater to rule (mark) the day and the lesser to rule the night.
So, the sun and moon are signs and for appointed feasts and for days and for years: -- Verse 14
Thus, Adonai Elohiym is and will always be the true Light of this world. Who really wants to walk in darkness if you truly have Him to guide you?