The following story circulated around in recent years, and just in case it still is, please be advised, according to the snopes.com website, that it is not true.
The story went something like this:
The song "The Twelve Days of Christmas" was written in England as one of the "catechism songs" to help young Catholics learn the tenets of their faith - a memory aid, when to be caught with anything in writing indicating adherence to the Catholic faith could not only get you imprisoned, it could get you hanged, or shortened by a head - or hanged, drawn and quartered.
The songs gifts are allegedly hidden meanings to the teachings of the faith. The "true love" mentioned in the song doesn't refer to an earthly suitor, it refers to God Himself. The "me" who receives the presents refers to every baptized person. The partridge in a pear tree is Jesus Christ, the two Turtle Doves = The Old and New Testaments; three French Hens = Faith, Hope and Charity, the Theological Virtues; four Calling Birds = the Four Gospels and/or the Four Evangelists; Five Golden Rings = The first Five Books of the Old Testament, the "Pentateuch", which gives the history of man's fall from grace; Six Geese A-laying = the six days of creation; Seven Swans A-swimming = the seven gifts of the Holy Spirit, the seven sacraments; Eight Maids A-milking = the eight beatitudes; Nine Ladies Dancing = the nine Fruits of the Holy Spirit; Ten Lords A-leaping = the ten commandments; Eleven Pipers Piping = the eleven faithful apostles and Twelve Drummers Drumming = the twelve points of doctrine in the Apostle's Creed.
Two very large red flags indicate that the claim about the "secret" origins of the song "The Twelve Days of Christmas" is nothing more than a fanciful tale, similar to the many apocryphal "hidden meanings" of various nursery rhymes: 1) There is absolutely no documentation or supporting evidence for this claim whatsoever, other than mere repetition of the claim itself; and 2) The claim appears to date only to the 1990s, marking it more likely an invention of modern day speculation rather than historical fact.
The utility of a Christmas song as a surreptitious means of memorizing a catechism would be quite limited, as its use would obviously be restricted to Christmastime. How was the supposedly forbidden catechism taught to children throughout the rest of the year? Where are the other rhymes and songs with similar hidden meanings that Catholics would had to have used for their catechism throughout the rest of the year?
There are no obvious relationships between the concepts to be memorized and the symbols used to represent them in "The Twelve Days of Christmas." In what way do "eight maids a-milking" remind one of the Eight Beatitudes? How are "nine ladies dancing" supposed to bring the Nine Fruits of the Holy Spirit to mind?
Without any obvious relationships between the symbols and the concepts they symbolize, this song is no more useful as a "memory aid" than simply memorizing the numbers one through twelve would be.
As one would expect to find in a folkloric explanation (rather than a factual one), there is a great deal of variation in the list of religious tenets supposedly symbolized in the song. The three French hens represent the three "theological virtues" (faith, hope, and charity), or maybe the Holy Trinity, or the three gifts the Magi brought for the infant Jesus. The four calling birds are the Four Gospels, or maybe the four major Old Testament prophets (Isaiah, Jeremiah, Ezekiel, and Daniel), or the four horsemen of the Apocalypse.
The five golden rings are the five books of the Pentateuch, or maybe the five decades of the rosary, or the five obligatory sacraments of the Church. A song genuinely used as a "memory aid" would be expected to have a standard, fixed form, not variation upon variation.
What we do know is that the twelve days of Christmas in the song are the twelve days between the birth of Christ (Christmas, December 25) and the coming of the Magi (Epiphany, January 6). Although the specific origins of the song "The Twelve Days of Christmas" are not known, its earliest known printed version was in the 1780 children's book 'Mirth Without Mischief'. (The song is apparently much older than this printed version, but we do not currently know how much older.) Textual evidence also indicates that the song "The Twelve Days of Christmas" was not English in origin, but French. Three French versions of the song are known, and items mentioned in the song itself (the partridge, for example, which was not introduced to England from France until the late 1770s) are indicative of a French origin.
The bottom line is this: "The Twelve Days of Christmas" is what most people take it to be: a secular song that celebrates the Christmas season with imagery of gifts and dancing and music.
Some misinterpretations have crept into the English version over the years, though. For example, the fourth day's gift is four "colly birds" (or "collie birds"), not four "calling birds." The word "colly" literally means "black as coal," and thus "colly birds" would be blackbirds .The "five golden rings" refers not to five pieces of jewelry, but to five ring-necked birds, such as pheasants. When these errors are corrected, the pattern of the first seven gifts' all being types of birds is re-established.
Nonetheless, plenty of writers continue to expound upon "the beauty and truly biblical and spiritual meanings locked away in this wonderful song that puts Christ into Christmas where he doesn't appear to be."
Don't misunderstand - Christ certainly belongs in Christmas - he is, indeed, the "reason for the season."
He just doesn't have a place in the song "The Twelve Days of Christmas."