Christmas carols: Gaudete!
"Gaudete!" (lit. "Rejoice!") was published in 1582 as part of the collection Piae Cantiones. (However, this source gives only the music for the refrain; the music used for the verses dates from an early 15th century source.) The text of the refrain means "Rejoice! Rejoice! Christ is born of the Virgin Mary; rejoice!" The verses celebrate God made man and include a reference to the gate of Ezekiel, a metaphor for the Virgin Mary. (She's worth a lot of metaphors, apparently.)
The text and music of the refrain have been criticized for being poorly matched — the first "Gaudete!" has the second and third syllables stressed, while the second "Gaudete!" lacks a stress on the first syllable (which is where it should properly be) — so other words are sometimes paired with this tune. Nonetheless, the original version remains quite popular.
Les Petits Chanteurs de Laval, 2007:
King's Singers, from their album A Little Christmas Music, 1990:
I found a video recording of the King's Singers performing this carol, but the quality was terrible, so I settled for this audio-only recording, instead.
University of Southern Mississippi, Carillon Handbell Choir, 2006:
Another audio-only version, this time instrumental.
Bonus track: Steeleye Span, 1973:
"Gaudete" was a 1973 hit single for British folk band Steeleye Span. Of course, it wasn't very representative of their other work, being that it was sung a capella and, you know, entirely in Latin. (It's got to be a bit harsh when you're best loved for being the least like yourself.)