Priests are devoted to the spiritual, and express their unwavering faith by serving the people. For millennia they have left behind the confines of their temples and the comfort of their shrines so they can support their allies in war-torn lands. In the midst of terrible conflict, no hero questions the value of the priestly orders. These masters of the healing arts keep their companions fighting far beyond their normal capacities with an array of restorative powers and blessings. The divine forces at the priest’s command can also be turned against foes, smiting them with holy fury.
As light cannot exist without darkness, and darkness without light, some priests tap into shadow to better understand their own abilities, as well as the abilities of those who threaten them.
Priests practice a complex, organized form of spirituality built around moral philosophy, the worship of a particular deity (such as Elune) in some cases, and/or idol worship, rather than around the reverence of the elements that shamans practice, or the close divine connection with animals and the wilderness that druids maintain. Priests serve not only as influential religious figures in their respective societies, but also as powerful practitioners of divine magic, which they use to heal and protect, or harm and weaken.
Devotion to the faiths of Azeroth leads many priests to the paths of courage and heroism. In dark times, priests carry the Light of faith with them as a reminder of the powerful forces at work beyond the comprehension of the peoples who walk the land. Powerful healers with an intimate connection to the divine, priests are empowered with abilities that aid them in times of dire need.
Priests comprise quite a varied group in Azeroth. A female priest is called a "priestess". Many are followers, in some manner, of the Holy Light. Some priests choose to be pyremasters or High Priest, while some of the most experienced become epic priests. There are also racial restrictions to some titles, such as witch doctor for trolls and Priestess of the Moon for night elf females.
While the draenei were the first known physical race to be associated with the forces of "The Light", humans were the first to discover The Holy Light on Azeroth, and were responsible for passing on the religion to other races, most notably the high elves and dwarves. Humans build mighty churches and cathedrals as places of worship and teaching of the Light. The religion teaches its followers to be virtuous in life, and while the religion is more philosophical than theistic, its practitioners do believe their devotion connects them to a greater and mysterious force in the universe. There is mention in older lore that divine beings known as "hope" guide The Light's worshipers with an unseen hand. Humans have produced great priests who have healed their allies or have used the powers of the Light to purge their enemies.
Forsaken who once followed the tenets of the Holy Light altered their philosophy upon their transformation. Forsaken have abandoned religion, just as they believe it abandoned them. Lost and hurt, these priests founded a new religion based on a self-centered version of their former faith. Dubbed the Forgotten Shadow, this philosophy centers around self-empowerment and a desire to balance life with death. While they can no longer use the Holy Light, and have since learned how to use the shadow; the priests teach that there must be a balance between light and shadow, and members must learn the Light as well, but never forget they were born from the shadow.
The troll priesthoods are, much like the shamans and the witch doctors of the various troll tribes, spiritual advisers and caretakers. With trolls being naturally superstitious and spiritual, it allows the various troll priests to manipulate the spiritual energy of the world in order to either heal or harm their targets. The various energies that the troll priests draw can come from various sources, be it Loa spirits, voodoo magic or the target itself. Drawing upon these energies, the troll priests either mend or harm, depending on which blessing the spiritual entity bestows. Arguably, in World of Warcraft, troll priests can be considered witch doctors in a cultural perspective, in equal terms with the shamans.