Word Puzzle

There's a five letter word
these clues can help you find.
The answer isn't "known"
but to some, the word is "blind".

It's more valuable than gold.
yet it's free to everyone.
More powerful than a train,
with it's engine on full run.

Although it isn't hidden
it is usually kept inside.
It is better than a compass
when you use it as a guide.

You either have it, or you don't.
There is no in-between.
It puts meaning into life.
It is felt, but can't be seen.

It can mend a broken heart.
Cure disease. even cancer.
It doesn't cost a dime,
and neither does the answer:


"FAITH"