Q: Our parish celebrates a 5:30 pm Mass on Sundays. On 12/31, would this Mass be for Holy Family or vigil for Mary, Mother of God?
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A: In the United States, January 1 is not a holy day of obligation when it falls on a Saturday or a Monday. Therefore, a mass on Sunday night, December 31, 2017, must be the liturgy of Holy Family. Sunday is the day of obligation, not Monday, and its liturgy therefore prevails.