MTed - one thing that might warrant correction. The Baltimore Catechism was published in 1885 as the official text for the religious instruction of Catholic children in the United States. While it was not in existence at the time of the 16th-century supression of Catholics in England, it was basically the same doctrine. I don't know that there was a catechism for the entire Roman Catholic Church until the Catechism of the Catholic Church was published in 1992.
I said in a previous thread (click) that I'm sure the song has been used for religious instruction (catechesis) because I heard a Jesuit priest use it in a sermon two years ago. I've taught catechism all my life, and I'll use anything as a catechetical device. In the olden days, I even stooped to using the songs of Simon and Garfunkel - but S&G don't work with kids any more (No, I did not go so far as to use the recordings of the Beach Boys for catechism, but I know people who did). As to whether "Twelve Days" was originally used for religious instruction, I kind of doubt it.
I think there's a need for more study of the history of this song. The Traditional Ballad Index dates the earliest known version of this song at 1780. In The Folk Songs of North America, Alan Lomax says this:

In old England, this song was sung on Twelfth Night as a Christmas game of forfeits. The players sat in a row, the first one singing the first round of the tune, the second the second, the third the third, and so on, until one made a mistake or named the gift wrongly. This player paid a forfeit. The song went on and one and the game continued until a number of forfeits had been accumulated. The forfeits were then counted and each owner had to redeem his fault by performing some task. Several versions of this game have been noted in the mountains of East Tennessee, but it normally occurs as a song.

Religious? I don't think so. I'm guessing that the interpretation Zorro posted in this thread is the pious invention of some mid-20th-century American. MTed, is the e-mail you received pretty much the same as what Zorro posted? If not, how 'bout posting it here?
I'd still like to see more information on the history of this song. What I've found is pretty sketchy.
-Joe Offer-