'show' pretty %B without a diff

Hey Mr(s) git show some good to me!

I'd like to output a comment in my script. Thus, I try: 'git show --format="%B" commitId' There is always diff in the end of the output. No matter what format I specify, even when it is empty. How can I avoid diff output in the 'git show'? Thank you.

73! Peter pgp: A0E26627 (4A42 6841 2871 5EA7 52AB 12F8 0CE1 4AAC A0E2 6627) -- http://vereshagin.org