Overview
In many Western Christian traditions, Midnight Mass is the first liturgy of Christmastide that is celebrated on the night of Christmas Eve, traditionally beginning at midnight when Christmas Eve gives way to Christmas Day. This popular Christmas custom is a jubilant celebration of the mass or service of worship in honour of the Nativity of Jesus; even many of those Christian denominations that do not regularly employ the word mass uniquely use the term "Midnight Mass" for their Christmas Eve liturgy as it includes the celebration of Holy Communion.
History
The tradition of a midnight Vigil on the eve of Christmas began in the East, and was observed in the late fourth century in Jerusalem by a Christian woman named Egeria on the night of January 5. The tradition reached the Western world in the year 430 under Pope Sixtus III in the Basilica of St Mary Major.
By the twelfth century, the practice of midnight Mass had become more widespread as all priests had been granted the faculty of celebrating three Masses on Christmas Day (previously reserved to the Pope), provided the three different propers were celebrated at their appropriate times of midnight, dawn and day.
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