Eaisly remove labels with a heat gun.

My dear friend  Paula passed this tip along to me a few years back:  Use a heat gun to easily remove labels from jars, and cans.  Heat it up a bit, but not too much.  You'll see the glue starting to melt.  Just wipe it off with a damp cloth.  Be sure to do this in a safe area, and make sure there is nothing laying around that may catch fire.  Always use caution!