While there is some dispute over this translation of the song, tradition has it that in England, between 1558 and 1829, Catholics were prohibited by law to practice their faith in public or in private. Until Parliament emancipated Catholics in England in 1829, it was illegal to be Catholic.
"The Twelve Days of Christmas" was a coded message written in England as a memory aid to help young Catholics learn the basics of their faith. Since the song sounded like rhyming nonsense, authorities would not know that is was a religious song and young Catholics could sing it without fear of imprisonment. The song is, in a sense, an allegory with each of the gifts in the song representing something significant to the Bible.
The song begins, "On the first day of Christmas my true love gave to me..." The "true love" repeated in the song doesn't refer to an earthly suitor, but to God himself. The "me" who receives the presents refers to the believing Christian.
The "partridge in a pear tree" is Jesus Christ upon the Cross. In the song, Christ is symbolically presented as a mother partridge because she would feign injury to decoy s predator away from her nestlings. She was even willing to die for them. The tree is the symbol of the fall of the human race through the sin of Adam and Eve. It is also the symbol of its redemption by Jesus Christ on the tree of the cross.
The "two turtle doves" refers to the Old and New Testaments of the Bible.
The "three French hens" stand for faith, hope and love -- the three gifts of the Spirit that abide, mentioned in 1 Corinthians 13.
The "four calling birds" refer to the four evangelists who wrote the Gospels -- Matthew, Mark, Luke and John -- which sing the song of salvation through Jesus Christ.
The "five golden rings" represents the first five books of the Bible, also called the Jewish Torah: Genesis, Exodus, Leviticus, Numbers and Deuteronomy.
The "six geese a-laying" is the six days of creation.
The "seven swans a-swimming" refers to the seven gifts of the Holy Spirit; wisdom, understanding, counsel, fortitude, knowledge, piety, and fear of the Lord.
The "eight maids a-milking" reminded children of the eight beatitudes listed in the Sermon on the Mount.
The "nine ladies dancing" were the nine fruits of the Spirit found in Galatians 5:22-23: love joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control.
The "ten lords a-leaping" represents the Ten Commandments.
The "eleven pipers piping" refers to the eleven faithful apostles.
The "twelve drummers drumming" were the twelve points of belief expressed in the Apostle's Creed: belief in God the Father, the Son and the Holy Spirit, that Jesus Christ was born of a virgin, made man, crucified, died and arose on the third day, that he sits at the right hand of the father and will come again, the resurrection of the dead and life everlasting.