I never need to see the sun again. Because you already light up my world.

Actually, you would need the sun in order to maintain constant temperature on your planet earth. Disregarding its function as such will cause the climate to fall out of balance and ultimately lead to the extinction of the human race.
And why would you look at the sun anyway. Staring at it will eventually make you blind, you know. I worry that your eyes will need a serious healing session if that comes to pass.
[sorry I slipped into naive!Castiel mode xD]
