Q: Halloween, Thanksgiving, and Christmas are coming up soon. My parish always decorate the altar and sanctuary like something from Good Housekeeping. Is this allowed?
A: I'm assuming here that you're talking about what I call "Martha Stewart Liturgical Decoration;" that is, a big nest of pumpkins and gourds in front of the altar, or one of those paper fan turkeys sitting on top of the tabernacle, etc.
Here's what the General Instruction on the Roman Missal says (italics mine):
73. First of all, the altar or Lord’s table, which is the center of the whole Liturgy of the Eucharist, is made ready when on it are placed the corporal, purificator, Missal, and chalice. . .
Even money or other gifts for the poor or for the Church, brought by the faithful or collected in the church, are acceptable; given their purpose, they are to be put in a suitable place away from the Eucharistic table.
305. Floral decoration should always show moderation and be arranged around the altar rather than on the altar table.
306. For only what is required for the celebration of the Mass may be placed on the altar table: namely, from the beginning of the celebration until the proclamation of the Gospel, the Book of the Gospels; then from the Presentation of the Gifts until the purification of the vessels, the chalice with the paten, a ciborium, if necessary, and, finally, the corporal, the purificator, the pall, and the Missal.
In addition, arranged discreetly, there should be whatever may be needed to amplify the Priest’s voice.
The bottom line here is that the altar represents Christ in the center of his Church and is not to be used as a decorating platform for seasonal holidays or miscellaneous objects associated with a feast day or a parish group.
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