In olden days, the Gods of Avalon favoured the rank of High Priest - similarly named across all divine Orders - as the sole 'leader' of their mortal followers. This has evolved, in modern times, with divinities deciding to form an Order wholly person to their own desires, role and outlook. The old rank of High Priest is retained by many and the notion of the priesthood is pivotal still (see HELP PRIESTHOOD) as representing those followers of most holy status, entrusted with powers and influence within the divine realm of their patron.
Type PRIESTS at any time to see a list of those mortals in Avalon and visible to you with priesthood status within their holy Order, and HELP HIGHPRIESTS to provide a list of the select group of mortals blessed with the highest of rank within their Order - the equivalent of the old High Priest, never held by more than a handful representing each deity and often in possession of just one illustrious Avalonian.
If you are fortunate enough to be given high rank in your Order, type PRIEST on its own to receive a list of commands given to you by your patron. Lower chapters/levels in the Order tend to have no special commands and it is usually only when the priesthood is entered that the PRIEST command becomes significant. Additionally, those who are members of their patron's priesthood may type PRIESTHELP to explore a help system specifically documenting the priesthood, its purpose, its commands, its potential powers and its influence on wordly affairs (both mortal and amongst the pantheon).
See also: HELP PRIESTS and HELP SUMMONING (for info on GO/SUMMON powers).