The Twelve Days of Christmas” celebrates the official Christmas season which starts liturgically on Christmas Day and ends twelve days later on the Feast of the Epiphany.
“My true love” refers to God, “me” is the individual Catholic.
The “twelve lords a leaping” are the twelve basic beliefs of the Catholic Church as outlined in the Apostles Creed.
The “eleven pipers piping” are the eleven Apostles who remained faithful after the treachery of Judas.
The “ten ladies dancing” are the Ten Commandments.
The “nine drummers drumming” are the nine choirs of angels which in those days of class distinction were thought important.
The “eight maids a milking” are the Eight Beatitudes. The “seven swans a swimming” are the Seven Sacraments.
The “six geese a laying” are the Six Commandments of the Church or the six days of creation.
The “five golden rings” are the first five books of the Old Testament called the Torah which are generally considered the most sacred and important of all the Old Testament.
The “four calling birds” are the Four Gospels.
The “three French hens” are the Three Persons in God or the three gifts of the Wise Men.
The “two turtle doves” represent the two natures in Jesus: human and divine or the two Testaments, Old and New.
The “partridge” is the piece de resistance, Jesus himself, and the “pear tree” is the Cross.