Religion2

Beliefs:

Polytheism: There are many gods, divine beings with immortality, both good and evil. Those which are good deserve veneration, especially the alicorns.

Afterlife: Those who are good go to Heaven [also called Elysium], which is envisioned basically as an idealized medieval equestria. Robes, crowns, fields of grain, cities of jewels, etc. Those who are evil go to Hell [also called Tartarus, which is DISTINCT from the Equestrian prison by that name], which is imagined as a vast pit of fire and brimstone. Those who are especially good, and follow the Celestine faith become "angels", alicorn-like beings with special status in the afterlife. Cherub/archangel/etc do not exist as concepts.

Morality: They follow the morality laid out in the Elements of Harmony and the show. Generosity, kindness, humility, compassion, etc, etc, etc.

Holy Books: The Celestine Faith lacks an authoritative text, but the "Book of the Sun" written during the Expansion Era contains a comprehensive list of common doctrines, hymns, and inspiring tales from history. It was originally written in Ye Olde Equish, but modern translations exist as well.

Titles: Each church is led by a priest, who bears a title such as Sister, Brother, Father, Mother, etc with no authoritative oversight on which it has to be. These priests in turn answer directly to the three Cardinals, who by tradition are taken one from each tribe, who in turn report to the High Cardinal, who can be from any tribe. These leaders advise and guide the faithful, but do not maintain a comprehensive canon, Celestine doctrine is flexible and individual. The concept of "saints" and "sainthood" does not exist in Equestria.

Prayer: The concept of prayer is a relic from earlier religions where the gods were less physically present, and is interestingly enough absent from the Celestine faith, on the simple technicality that if you want to talk to Celestia, its infinitely simpler to just drive to Canterlot. Nonetheless, oaths such as "With Celestia as my witness!" and simple calls for help such as "Gods help me!" still exist.

Places of Worship: The Celestines worship in churches, temples, and cathedrals which dot Equestria.

Dominion: The Celestines dream of a pan-Equine state that would encompass the three tribes and bring all ponies under a single banner. In modern times, this dream is generally considered realized with the modern Equestrian State, and delusions of expanding it further are considered unnecessary. In this regard it is essentially like the real world concept of Manifest Destiny.

Nightmare Moon: In medieval theology, Nightmare Moon was a demonic figure, placated with grain sacrifices once a year. This sacrifice was eventually bastardized into the Nightmare Night Festival. With the return of Princess Luna, this doctrine, already on its last legs, has begun collapsing.

A Note on Secularization: The above religion was mostly practiced in force in the Expansion Era. During the transition to Modern, Celestia was increasingly viewed as teacher, leader, and friend as opposed to a matronly goddess [while the latter remained orthodoxy], and the 'religion' of the Equestrians gradually gave way to a less serious, secular faith in the princesses. Most modern ponies view 'the gods' with the obsessive celebrity of nobility, rather than outright worship. At least when they're not at church.