Answer:
I know a word of letters three, add two and less there will be.
I am not alive, though I never die, to no one I've ever told a lie, today I can be god's warrior, and serve him with no horror, but tomorrow I might be devil's knight, for I am what ends the light.
What has only two words, but thousands of letters?
You have it even if there is none.
What can be seen but not touched?
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.