Don’t groan – forget John Julius Norwich – once it had a different meaning:
“From 1558 until 1829, Roman Catholics were not permitted to practice their faith openly. Someone during that era wrote the Twelve Days of Christmas. It has two levels of meaning: the surface meaning plus a hidden meaning known only to members of their church.
Each element in the carol has a code word for a religious reality which the children could remember.
• The Partridge in a Pear Tree was Jesus Christ
• Two Turtle Doves were the Old and New Testaments
• Three French Hens stood for Faith, Hope and Charity
• The Four Calling Birds were the four gospels
• The five Golden Rings recalled the Torah, the first five books of the Old Testament
• The Six geese-a-laying are for the six days of creation
• Seven swans a-swimming represented the seven gifts of the Holy Spirit; prophesy, serving, teaching, exhortation, contribution, leadership and mercy
• The eight Maids a-milking were the eight beatitudes
• Nine ladies dancing were the fruits of the Holy Spirit: Love, Joy, Peace, Patience, Kindness, Goodness, Faithfulness and Self Control
• Ten Lords a-leaping were the ten commandments
• The eleven Pipers Piping stood for the eleven faithful disciples
• The Twelve Drummers Drumming symbolised the twelve points of belief in the Apostles’ Creed”
From https://www.catholicnewsagency.com/resources/advent/customs-and-traditions/the-history-of-the-twelve-days-of-christmas
The Twelve Days of Christmas