Also, Magic should be magical. Therefore i have always despised the treatment Magic receives under most of the rule systems available on the market: hence, in my world, you'll never find any trace whatsoever of wizards throwing fireballs or flying in the sky. In my view Magic is something FAR more mysterious, much rarer, and much risky.
It exists, but it is totally cloaked in mystery, almost unapproachable by humans. If you really dare studying it, be prepared to lose your soul or something similar.
See for instance the opening phrases in Land of the Rising Sun rpg:
Definitely, it sets the tone and you are instantly transported in a faery-realm, so to speak, quite different from the one we are used to (magicians depicted as battle machines).
So, to reiterate, Magic is the most important thing in a role-playing game that is of the Fantasy type, and Magic should be magical, otherwise it is spoiled of all its fascination and charm, it loses its potential and it doesn't succeed in conveying the sense of wonder and mysticism it ought to possess.
That said, if magicians in my campaign are very rare (and it is nigh impossible to have one as a player character- because to me that would amount to let a player run an Istari like Gandalf in my world), Priests of any kind are even rarer- to the point that they just don not exist anywhere.
I totally removed the priest class. Why?- you might ask.
Well, the point is that they wield a power that is even more fabulous- a power man is not meant to know, ascertain, nor comprehend. We are entering here in the Divine Realm.
Whereas Magic and the occult science is an esoteric kind of science, priests devoted themselves to the ineffable and the Divine.
This kind of distinction is always underrated. How could i blame this fact if even what i consider an obvious, self-evident truth about Magic is underrated? (See what we said about it before).
Put in another way, if Magic is mysterious, the Divine is mysterious up to the point of being unfathomable.
As i made in some previous articles (you'll find a list of these at the bottom of this post), i will relate a story which explains all this.
St Cyprian was a pagan and a native of Antioch. From his early childhood his misguided parents dedicated him to the service of the pagan gods. From age seven until thirty, Cyprian studied at the most outstanding centers of paganism: on Mount Olympus, in the cities of Argos and Tauropolis, in the Egyptian city of Memphis, and at Babylon. Once he attained eminent wisdom in pagan philosophy and the sorcerer’s craft, he was consecrated into the pagan priesthood on Mount Olympus. Having discovered great power by summoning unclean spirits, he beheld the Prince of Darkness himself, and spoke with him and received from him a host of demons in attendance.