Warp and Woof?

I was reading the J-Walk Blog and saw something interesting at the bottom of this entry. Here is an excerpt:

My favorite quote, from a VP at Zondervan:

"A lot of people read the Bible because it's obligatory, something to keep God off their backs. We're looking to turn them into Bible lovers ... so it becomes part of the warp and woof of their being."

Warp and woof? I've never heard that expression. It's actually a weaving term. I need to figure out how to use that in an actual blog post

I know warp, but woof? I've always called it warp and weft.

Anybody care to weigh in?