As a lamentable result of the double darkness into which most Catholic musicians have been born - fear of Latin, and ignorance of the Propers of the Mass - many of them are entirely unable to explain why this, the Third Sunday in Advent, is called 'Gaudete Sunday'.
"Gaudete" means "Rejoice" - that's the sum of their knowledge. So they tend to plan music which involves the word "rejoice" in some way, the foolproof "word-association" method of liturgical planning which works all the rest of the year. Unfortunately, on Gaudete Sunday there is a pitfall which it is very easy to fall into:
That's Steeleye Span, singing the medieval carol 'Gaudete, Christus est natus'. Church musicians, fondly remembering the Steeleye Span phase of their 1960s youth (and there's nothing wrong with that, I like Steeleye Span myself... outside church), jump on this carol as the perfect thing to sing on Gaudete Sunday.
So do you see the pitfall, right there in the title? Indeed. It has "Gaudete" in there, which sounds right - but should we really be singing that "Christ is born" on the Third Sunday in Advent?
No. We shouldn't.
The name 'Gaudete Sunday', like many of the traditional names for Sundays in the Church's year, comes from the first words of the Introit:
Gaudete in Domino semper: iterum dico, gaudete: modestia vestra nota sit omnibus hominibus: Dominus prope est. Nihil solliciti sitis: sed in omni oratione petitiones vestrae innotescant apud Deum.
"Rejoice in the Lord always; again I say, rejoice. Let your forbearance be known to all men; the Lord is at hand. Do not be anxious for anything, but in all manner of prayer, let your requests be made known unto God."
It's not difficult to see why this is more appropriate for Advent - 'the Lord is at hand!' - than a carol which rejoices in the birth of Christ. The reason this is so often forgotten is that most churches no longer sing the Introit. Which is a shame, because - listen to it!:
It goes against everything in me to be advising against the use of a medieval carol in any context, let alone discouraging the use of Latin in church, but nonetheless: 'Gaudete' is an inappropriate song to sing this Sunday. Don't do it. Save the carol, which is lovely, for Christmas, and do your bit to keep Advent as the distinctive season it really is.
Oh, and: rejoice! The Lord is at hand...