You know, I think I could get behind a game in which the player actual is Jesus 2.0- a teacher-figure of such huge cultural/historic importance that an entire religion forms after you and goes on to shape history as it displaces other religions and philosophies.
Heck, you could even have an entire franchise on it, in which sequel game PCs are Saints or Prophets or such, other influential figures in the movemen. The philosophy or way you set out to teach as Jesus 2.0 naturally gets warped or changed by the remembrance and activities of the followers, and evolves in new historic contexts. Then the PC of the new game, who will ultimately be a Saint or something similar, becomes key in shaping how the sect evolves over time and circumstances. Do you try to return to the roots and do what Jesus 2.0 preached? Or do the new lessons and contexts call for a change in interpretation? With time skips and such, you could have various cascading Consequences from your theological choices in the previous games.
For example...
In game 1, you are Jesus 2.0, no doubt in a time of upheaval and uncertainty. The Old Gods don't seem to be working out so well, trouble is everywhere, and you (the PC) gather a following as you help set things right and spread lessons. Your example inspires others to follow you, creating a community. As Jesus 2.0, your Big Decisions are the events that history remembers that help codify your major beliefs of the belief systems. Some things might be 'do you claim to represent the divine or not?', or 'is justice mercy or punishment?' or 'should we accept converts to our way?'
In game 2, the community/sect is established and growing and traditional. Jesus 2.0 is revered but gone, and 'WWJD' is one of the questions of the time as the Sect comes into contact with an Outside Religion. The plot of the game focuses on the friction and interaction between the Sect and the Outside Religion, with differing consequences based on J2.0's tenants. Say that the Outside Religion is polytheisti, but J2.0 is explicitly non-divine (aethiest philosophy)- conflicts break out that might have otherwise been avoided if J2.0 claimed divinity, which Outside Religion might have gone 'oh, just another god then. Cool.' Prophet the PC, the new PC, gets to lead/influence how the Sect and how the Outside Religion interact- with outcomes ranging from 'religious war' to 'coexistence' to 'assimilation and combination.' Along with that big Precedent of how to handle other religions, the Prophet gets to set new principles of the religion. Stuff like 'non-violence' and other ideas.
In game 3, the community has emerged from the events of game 2 and faces a new, greater threat: religious cleansing where coexistence doesn't seem to be possible. An outside religion is trying to wipe yours out. The sect is in a time of crisis. The Holy Warrior, the new PC/religious figure, dabbles with the military dimension of politics and religion. If your previous prophets were all 'let's be a peaceful religion,' how does that square with the PC (and other people) who have to fight to survive: does the religion die? Do you create rationalizations for the defense of the faithful? Do you outright overturn such earlier idealism in the face of new threats?
And so on.