I found this verse several years ago in a Love Comes Softly book, and I've loved it ever since.

Isaiah 41:10
  "Fear thou not; for I am with thee: be not dismayed; for I am thy God: I will strengthen thee; yea, I will help thee; yea, I will uphold thee with the right hand of my righteousness."

I read it before I underwent treatment for cancer, and it wasn't until after treatment that the words really struck me.

  God never leaves us. Even when we have all the reasons in the world to believe that he has. I know I'm just a stranger on the internet, but I know this to be fact.

I know this because God has never abandoned me. Even when I'm at my worst. I see his presence in the butterflies outside, in the gentle tender mercies I receive each day.

To me, nothing is more comforting than that verse.

What is your favorite Old Testament verse?