Dictionary/Ecclesiastical/Color of Vestments
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Color of Vestments. In her vestments the Church employs five different colors. On the feasts of our Lord, of the Blessed Virgin, of the angels, and of those saints who were not martyrs, she makes use of white, not only to signify the stainless purity of the Lamb and of His Virgin Mother, but also to symbolize the "great multitude, which no man could number, of all nations, and tribes, and peoples, and tongues, standing before the throne and in sight of the Lamb, clothed with white robes" (Apoc. vii. 9). On the feasts of Pentecost, of the Finding and the Exaltation of the Cross, of the Apostles and martyrs, she employs red, to signify those fiery tongues that alighted on the heads of the Apostles when the Holy Ghost rested visibly upon them and in reference to the effusion of blood by Christ and His followers. On some Sundays (when the office is of the day) the vestments are green. Purple is the color assigned for the penitential times of Advent and Lent, for the Ember days, and for several vigils throughout the year; while black is reserved for the office of Good Friday and Masses for the dead. Rose color is used on Gaudet and Laetare Sundays; and on the fourth Sunday in Advent, when it falls on the 24th of December. Cloth of gold may be substituted for white. Yellow (color flavus) and heavenly blue (color cæruleus) are expressly forbidden (S. R. C. 16 Mart. 1833 in Veron).