Hello all!

First time poster here.  Working on a campaign story centered in the forgotten realms world with a Holy War being the major world event going on that our adventurers will weave in and out of throughout their adventures.

General idea I have is 4 major religions with 1 being the most dominant and backed by most of the major cities and military, 1 being pretty prominent but less backed by major governments, 1 is nature based and is worshiped along the outskirts and wild lands and the 4th one is a more cultist darker religion of the underground and the oppressed.

a major plot twist i want to include is that the most dominant religion preaches very righteously but many of the high ranking officials who are in that "clergy" have more nefarious schemes than the good aligned religion they lead.

Here's where some of my roadblocks and questions come in.  How would a good aligned deity feel about those under their worship acting out of character to the faith? Would it have an effect on their powers etc.? Have people worked with having a deity imprisoned (as an idea of maybe the actual good deity is imprisoned in some way by the more nefarious members)?  

Basically i've never really dealt with the theology of DND too much before and that's one of the reasons this Holy War campaign really intrigues my creative juices... i just need to get through some of these "Well what about...?" roadblocks in my mind.  

Thanks for the help in advance!

I think your imprisoned idea would work nicely. In a world where gods grant mortals power a good diety would deny powers to evil followers, the gods in the realms, and most other settings are very active and alert.

But with your imprisoned idea, What if the good God was captured some how and a evil God took over his place. Now this evil God has the power of all the good gods faithful, and declares a holy war to stamp out evil, but in reality to control all the world, mwahaha, felt the need for a evil laugh.

that's something i was thinking, how have people who have done something along this line worked the imprisonment angle?  I think the easiest to do would be to have the other evil aligned god be the one who did the imprisonment and devote followers guard the means of which the adventurers could release the god.

I would agree with you. Some ancient artifact has him imprisoned on some other plane. The pcs could start as followers of good God, partake in the holy war and realise that what they are doing is wrong. Eventually they find out what happened, and how to free their God.

Maybe a pact of all the evil gods keeping him locked up, the pcs need to weaken the pact by turning each God against each other, then they brave the planes and free him, or her.

PCs will be adventuring in and around the conflict but unless they choose to will likely not be directly involved in it.  My hope is to give them the plot twist that as they do side missions and quests for some of the followers of the main religion the seed of doubt begins to get planted by other NPCs that appearances can be deceiving and eventually let the reveal occur that they've maybe been helping the wrong side (if they chose to help in the first place)

In my book, the PCs should be at the center of any campaign, at least eventually. Starting in the periphery and over time be at the heart of things. Introducing key factors early on that much later reveals themselves as major plot points is also a welcome twist. I think you have an excellent opportunity in that regard with your scenario. For example:

Start with a simple encounter. The PCs are in a remote area and stumble upon a  hermit in tatters that is attacked by some goblins or such. He cries for help. He is wounded, thanks them but cannot offer anything as a reward. His behavior is odd and quite surly and mean. Far from thankful. He can mention that as far as he knows the goblins have a camp further along, which might be easy to plunder now. Then, he leaves. Let him give the impression of an ungrateful bastard. 

> This is actually the good god, reduced to a weakened state by the ancient artifact and a not yet completed ritual. He escapes, too weak to even fight the goblins. The religiously order pursues him. 

A short while later the PCs meet a band of clerics and paladins of the good god with several dead and wounded. Asks PCs about the hermit. They claim he attacked them. They tell the PCs that the hermit is a demon in human form that have deceived them. Understanding how weak and wounded he is, they set off at once. Ask the PCs to help as they should redeem themselves after rescuing such a being. 

When finally cornered, the clerics perform the last part of the ritual. The hermits eyes blaze and shriek with an unworldly voice. He vanished and they thank the PCs, saying they have been part of a great deed for the good god. Anyone who speak Celestial can recognize the shriek as a drawn out “No!”

The PCs probably feel like the good guys, having helped clerics and paladins of a known good god. The order praises them and can set them on additional tasks. For a while they can act as a quest giver, simply put. 

The actual religious conflict could start like an avalanche from some trivial violent event. Preferably one that involves the PCs. Think Duke Ferdinand and WWI. Let’s say a minor conflict where some of the other order (?) are killed. Then let the PCs adventure somewhere else and just hear rumors of strife. When they return, they find out that the event the took part in triggered the war. This could be orchestrated with the order asking them for aid in various matters. 

Piece by piece the truth can later be revealed and towards the end, not only have the PCs been the ones lighting the spark for the war but also, before that, actually helping the bad guys “lock up” a god.