Stanley is Protestant. Here is an excerpt from his talk.
"For example, I often point out that at least Catholics have the magisterial office of the Bishop of Rome to remind them that disunity is a sin. You should not overlook the significance that in several important documents of late, John Paul II has confessed the Catholic sin for the Reformation. Where are the Protestants capable of doing likewise? We Protestants feel no sin for the disunity of the Reformation. We would not know how to confess our sin for the continuing disunity of the Reformation. We would not know how to do that because we have no experience of unity."
image - http://www.andyrowell.net/andy_rowell/2009/03/comparing-stanley-grenz-and-stanley-hauerwas.html