I do not know if there is a pattern, but there are some pictures online with a explanation of the meaning.
http://www.lutheran-resources.org/Luther_rose.htm
http://www.goodshepherd.nb.ca/seal/
http://en.wikipedia.org/wiki/File:Thueringen-Cobstaedt-Kirche-Fenster-2.jpg
I think the last one would make a beautiful quilt.