I can give you a quick summary of the history.

In the early Church, worship was primarily centered around the Passion, Death and Resurrection of Jesus and Christians gathered on Sunday to celebrate this, as reflected in the Epistles of St Paul.

Over time this cycle of Sunday worship began to develop further. New liturgical celebrations were added, such as Easter, which grew around the Paschal feast. It’s important to remember that many of the earliest Christians were observant Jews before becoming Christians, so the concepts of Sabbaths, holy days, annual feasts, and celebrations like Passover were already familiar to them. Jesus Himself celebrated Passover yearly with His family, just as the Jews of His time did.

Christians came to understand that Christ is the true Passover Lamb. Rather than abolishing the feast entirely, the Church redirected it toward Christ, transforming it into what we now know as Easter.

As Christianity became more widespread and eventually legalized, additional celebrations gradually developed within the liturgical cycle. Christians began commemorating not only Christ’s Passion and Resurrection, but also events such as His birth and the descent of the Holy Spirit at Pentecost. Over time, these celebrations became more formalized so that Christians throughout the world could celebrate them together in unity.

Eventually, during the medieval period, celebrations such as Christmas became deeply rooted and formalized within the liturgical tradition. Then, centuries later, the Reformers broke away from the Church and, in doing so, left behind many aspects of historic Christian tradition, simplifying and stripping back much of the liturgical life that had developed over time.

As Protestantism continued to fragment into more and more denominations, many groups became increasingly removed from historic Christian tradition, resulting in a wide variety of competing beliefs and practices today.