Q: We have always had the tradition that during Advent and Lent the organ is only used to accompany the voices, except on Gaudete and Laetare. Someone came to me recently asking if I had the source on that. I’ve looked in the General Instruction, but could not easily find it. Would you know that reference?
Amid your many things to do these busy Advent days, this is a small matter. However, I would like to answer this person with something in a written source. If that is something you have easily at hand, I would appreciate an answer, but only if …..
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A: The paragraph you want is GIRM 313.
313. The organ and other lawfully approved musical instruments should be placed in a suitable place so that they can sustain the singing of both the choir and the people and be heard with ease by everybody if they are played alone. It is appropriate that before being put into liturgical use, the organ be blessed according to the rite described in the Roman Ritual.
In Advent the use of the organ and other musical instruments should be marked by a moderation suited to the character of this time of year, without expressing in anticipation the full joy of the Nativity of the Lord.
In Lent the playing of the organ and musical instruments is allowed only in order to support the singing. Exceptions, however, are LaetareSunday (Fourth Sunday of Lent), Solemnities, and Feasts.