There are many factors to the rise of the Christian Church. A main development was the institution of bishops and archbishops to watch over the people and the churches. Probably a bigger factor was the rise in the power of the Pope. This came mainly from the Petrine Theory, which states that after Jesus gave the keys of the kingdom to Peter, basically making him a "Pope", all Peter's descendants would the next Pope, meaning the Pope had power directly from God.
Another major factor was the development of Monasticism. This helped because many monks became missionaries who spread Christianity even further, and boosted the power of the church. Monks would also copy the Scriptures, making it possible for more people to read them.
Gregory I was the father of Medieval Papacy, and formed the Papal states, which served as buffer zone between Rome and the rest of the world.
But along with all this came trouble for the church too. This came in the form of heresies. Two major heresies were these:
- Donatism: In this heresy, personal holiness or purity validated a church office. This meant that if you were baptized by a preacher who was later proven to be sinful in some major way, then that baptism would be worthless, and you would need to be baptized again.
- Arianism: This heresy says that Jesus was created by God and is therefore less than God, not equal to him.
There were also four men, the Latin Fathers, who were a major influence in the rise of the church. Their names were Augustine, Jerome, Ambrose, and Benedict. Augustine wrote two books, "Confessions" and "City of God", and was the bishop of Hippo. His books were a major influence for people later like the Reformers.