HT: Ryan Reeves
The earliest dating of Advent is impossible to determine. The start of Easter in Christian history is far more obviously tied to Passover (albeit with different methods for dating), and Christmas came to be associated with the birth of Christ as a result of it falling during the December Solstice, the darkest day of the year in the northern hemisphere. The coming of the Light of the World made a lot of sense in so much darkness. Within a few centuries of church history, both Easter and Christmas took on special meaning due to their use in commemorating the life of Jesus.
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