Ever since the split between the Catholics and Orthodox, and then alter the Catholics and Protestants, every Christian has desired a united Church. This is just a theoretical 'Christian Church'. :p Culturally, Christianity would go back to a more Jewish identity. Ditching some components Jesus told them to, and adding the celebrations of Easter/Christmas (Though preferably, they would be inspired by Jewish celebrations, and not Pagan ones). While balancing all the beliefs of the many different denominations would be difficult, it is theoretically possible, and necessary for a balance church. It cannot force the ideas of one man upon everyone else, but also can't let people abandon basic scripture. The Clergy would select a couple options for Pope who would all run to be Pope. Every Christian who has joined a Church would be allowed to vote. The Pope would settle disputes, excommunicate the greatest sinners (Church officials who are corrupt, or those who have found Jesus in their hearts only to lead others astray), hold ceremonial duties, etc. He/she would have respected opinions on theology, however, except for the foundations (Holy Trinity, Resurrection, etc), he would not have 'final authority' on matters of the Faith. Every denomination would be abolished in favour of every Church (Christian Community) getting freedom to believe what they want, except for going against the foundations of Christianity. Every Church has a founding document, laying out the organization of the church, how it operates, etc. 'The Church' will have a light tax on every Church, with all the Churches around the world, that should be enough money for operations. The Church would also heavily rely on donations from people. To prevent corruption, there would be several reforms, such as limiting how much money a Church official can make and an anti-corruption element of 'The Church' investigating Church Officials for corruption in all forms. For sinning and going against the oath they made with Christ and the Lord. 'The Church' would use its wealth to build new Churches across the world, pay for expeditions to spread Christianity, keep poorer Churches afloat, feed the poor, etc. They would also fund the 'Holy Order', a section of 'The Church' which is dedicated to military efforts. The 'Holy Order' would be a collection of Christian volunteers from all over the world. They would receive training from the Swiss Guard to defend Churches and the Holy Land. In case a Christian country is embroiled in war, the 'Holy Order' would be sent to act as peacekeepers, sacrificing themselves if needs be to protect Christian Communities. It would be purely defensive, with it's tactics and weaponry based around that concept. 'The Church' would govern, or share governance of Holy Lands. This includes the Vatican City, Byzantine, Jerusalem, Bethlehem, etc. They would let locals help decide the Government, however, the Church would exhibit significant influence. Based on the teachings of Christ, the Church would create the best cities they could. Basically, a return to how the Church originally worked with some reforms for the Modern Era. The only ones with religious authority are Christ, the Bible and the Apostles.
