An ancient tradition has it that clerics who fought in battles in bygone times were armed with maces only in order to avoid shedding blood. This custom of 'sine effusione sanguinis' appears to be based almost entirely on a lesser-known part of the Bayeaux Tapestry which depicts Bishop Odo wielding a club-like mace at the Battle of Hastings.

This ancient tradition found new favor among modern fans of Dungeons and Dragons Games which, early versions, similarly restricted the power of the Cleric Class to wielding on bludgeoning weapons in battle. This 'rule' has since then been widely imitated.