The Catholic Church tends to emphasize the need for adequate spiritual preparation before any major feast. Whether its Christmas or Easter, the Church urges its members to prepare their hearts for an encounter with the Lord.
Christmas in particular has retained many popular devotions and traditions that go above and beyond the normal Advent preparations.
St. Andrew Christmas Novena
This "novena," is called by many names, such as the Christmas Novena, St. Andrew’s Novena, St. Andrew’s Christmas Prayer, or the Christmas Anticipation Prayer.
In reality, it is not a traditional novena, as it is a full 25 days of preparatory prayer (novena means nine). Yet, it takes on the spirit of a novena by helping souls prepare for the celebration of Christmas.
The history of this novena is over 100 years old and is often printed with a date of 1897. It consists of praying a special prayer 15 times every day.
The number 15 may seem arbitrary, but as the author of the website Christmasnovena.com points out, "The number 15 reminds me of the original 15 decades of the Rosary, which was itself seen as a potential simplified version of praying the 150 psalms that are still sung by religious in monasteries and convents praying the Divine Office."
In this way, reciting this prayer 15 times unites us with that ancient custom of praying the Psalms as well as recalling the beautiful tradition of the Rosary.
The Ancient Christmas Novena
Prior to the St. Andrew Novena, the Church was more focused on the 9 days the precede Christmas. The number 9 represented the 9 months Jesus was in the womb.
The Catholic Encyclopedia gives a brief history of this ancient novena.
This included a number of devotions, including the O Antiphons, as well as the celebration of 9 consecutive Masses in honor of Our Lady.
The O Antiphons are even older than these later traditions, but constitute a long-lasting custom of preparing for Christmas in a spiritually focused way.
Whatever novena you may choose to participate in, the Church highly recommends a period of intense spiritual preparation in the days before Christmas, doing all that you can to make the celebration one that reaches the depths of your heart.