This verse fascinates me. Every time I read it I get something different from it. Maybe because every time I read it I am experiencing something different in my life.
To add even more dimension, you can say this verse ten different times each time emphasizing a different word in the verse and it will mean something different. For example:
"I can do all things through Christ which strengtheneth me."
"I can do all things through Christ which strengthenth me."
Same verse that can mean two different things to you depending on the emphasis. I think that is why this verse is such a comfort to so many people.