Sacred Vows

[Drogan Tome]

I am building a religious order for my campaign and it got me thinking that to make them more unique they would have sworn a sacred oath toward their goal (ridding a region of demonic influence and cleansing the land of taint).

This got me thinking that while I could give them an oath or two for flavor reasons I would like to have that mechanic in my game for future character and NPC options. Organized religion is templated from the Middle Ages Catholic Church with clerical variety coming from the patron saints that a cleric swears to.

I have been looking online and for Pathfinder all I can find are the monk vows which I could retool for my needs but I was hoping maybe some of you have already done work in this area and wouldn't mind weighing in.

I like the spirit of 3.5 exalted handbook feats but find them clunky mechanically.

Have any of you come up with something that works well in your game?

[Mysterious Stranger]

Sounds like the Oath against Fiends archetype for Paladins.

[Azothath]

there are several mechanics within PF1;
Paladin oaths
variant channeling
Deific Obedience (listed under the deity such as Nethys - see evangelist, exalted, or sentinel prestige class).

see also
Stormbringer RPG c1981 which lists acts to gain/lose Elan (% divine aid or intervention) in Chp 6.
in DnD Greyhawk they did Saint Cuthbert which was rather christian.
The Game has avoided active real world religions and dogma due to the obvious negative PR consequences(facts and opinion don't always meet).

[Goth Guru]

Taking a vow to a specific goal of a deity or demigod, would cause the trait True Believer. This would open up functions of items and possibly spells such as prayer beads, alters, and holy symbols.

They would get some conditional modifier verses temptation and other mental influences contrary to those goals. They could sanctify holy symbols. Crafts men or women who wish to make sacred magic items would have to take vows even if they take no levels in clerical classes.