DDSB Saint of the Day for December 21
Saint Thomas the Apostle is commemorated on this day in the Western Church. Daily Divine Service Book gives both the traditional Western propers and those incorporated in LSB, the latter in square brackets.
Though the older system of the ranking of feasts (as used in DDSB) would appear to allow St. Thomas' day to outrank the fourth Sunday of Advent, the modern custom of leaving the Sunday of Lent and Advent inviolate is to be preferred. The next time December 21st falls Rorate Coeli, it would be appropriate instead to commemorate St. Thomas with a second collect.
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