Before the events of the First War, the mission of the Holy Order of Northshire Clerics of Northshire Abbey was to spread the message of the Holy Light to people of the Kingdom of Azeroth. Following the invasion of the Horde which triggered the First War, Archbishop Alonsus Faol led the clerics into battle to aid the people of the kingdom. The clerics, although brave and powered by both healing and destructive powers of the Light, were unprepared for the dangers of war, and suffered heavy losses. This, following the end of the First War in orcish victory, prompted Faol, along with his apprentice, Uther Lightbringer, to found the paladin Order of the Silver Hand. The paladins, although possessing spirit of the clerics preceded them, were mighty knights talented in the arts of war. The Order of the Silver Hand greatly helped the Alliance of Lordaeron to overcome the Horde's might during the Second War. After the end of Second War, Archbishop Faol returned to his native Azeroth, which would be known as the Kingdom of Stormwind in the following years, to aid in its reconstruction. A new clerical order, comprised of clerics, priests and paladins, was founded: the Brotherhood of Northshire.
- See Belief retcon.
In "Warcraft: Orcs and Humans", the Clerics of Northshire are described as believing in "God", "angels", "daemons", "Hell", and "Heaven". This is continued through into Warcraft II, with references to "God", "angels", and "heaven". A reference to "God" is also in the church building's sound in the game, "Deo Gratias" (Deo Gratias), Latin for "Thanks [be] to God", which is a traditional cathedral hymn, fitting the image of holy paladins in the game.
The traditional view of Hell and God is also alluded to in the novels as well, for example in Day of the Dragon several of the paladins describe things by using religiously colored terms;
"A paladin had indicated to Rhonin that he believed that, after death, the mage's soul would condemned to the same pit of darknes shared by the mythical demons of old. This no matter how pure Rhonin's soul might have been otherwise."...a damned soul...devilish kind...
The religious structure and practices also keep in time with typical European medieval and even some modern Catholic structures and thought, such as the places of worship being called chapels, churches, abbeys, monasteries, and cathedrals.
Also typical Christian and Catholic clergy names are employed, even up to World of Warcraft, such as some male priests being called "Father" and "Brother" and prelature ranks such as Abbot, Bishop ,and Archbishop.
Like the practice of the Catholic Pope, archbishops take on a special name when they take office. Like Jarl, becoming Archbishop Benedictus.
Also, in the original Warcraft and Day of the Dragon something similar to the practice of Confession is described, as mentioned in the description for the cleric's invisibility cast (as a tool to make the confessing of secrets that weighed heavily upon the souls of worshippers easier to speak) as quoted from the guide, and in Day of the Dragon when Rhonin is asked to confess his sins to bring peace to his damned soul.
Though all this could just be put on the developers and writers trying to make the stories seem more "Medieval" with no real implications to actual religion implied. Although it does seem that in later versions of Warcraft the developers halted most references to anything that could be tied to any actual religious practice, and made the "Light" ambiguous in nature, so one could not really label it as being a parody or impersonation of any particular religion. In World of Warcraft and later games, followers of the Holy Light are described as following the Holy Light and any reference to "God" is not found. However, in Warcraft III "angels" appear during the Resurrection spell, and "angels" are still alluded to in World of Warcraft.
It is possible that the Clerics and some Knights of the Silver Hand found their basis of this "God" from one of the creation myths of Azeroth, as well as knowledge of the angels. Several references state that some in Azeroth believe that the universe was created by "a singular, all-powerful entity".