Many games and stories that draw upon medieval history tend to claim that priests use maces because they do not spill blood.
Wikipedia provides a citation for this on the Mace page, as does the page on the Cleric class (uncited):
It is popularly believed that maces were employed by the clergy in warfare to avoid shedding blood 2 (sine effusione sanguinis). The evidence for this is sparse and appears to derive almost entirely from the depiction of Bishop Odo of Bayeux wielding a club-like mace at the Battle of Hastings in the Bayeux Tapestry, the idea being that he did so to avoid either shedding blood or bearing the arms of war.
Is it true that priests or other members of the clergy used maces and other blunt weapons in combat, as opposed to edged weapons, for this specific reason?