Fr William Saunders (in his work “Celebrating a Merry Catholic Christmas”) discusses animals in relation to the Nativity and Christian life. He said there is a tradition in the Church that the donkey that Jesus rode on Palm Sunday followed him also to Calvary:
The nativity reminds us that there were the animals too. They were part of God’s creation. Sheep were raised for wool, so each was precious. They were also raised for the Temple sacrifices, like those at Passover. Sheep came to adore the Good Shepherd who himself came to gather us into the Church, his flock, and into God’s love. We too must remember that each of us is precious in the eyes of the Lord, and we are a member of the flock, the Catholic Church that our Lord founded upon the apostles.
Sheep were raised for sacrifice, and St. John the Baptist identified Jesus as the Lamb of God. Jesus said, “I am sending you like sheep in the midst of wolves” (Mt 10:16). Yes, there are those who would like to devour us, as they did the martyrs; nevertheless, we are called to be martyrs, witnesses of the Faith for others. And like the martyrs, we must cast off fear, for Jesus promised to be with us “until the end of the world” (Mt 28:20). To be effective witnesses, we need to know and to cherish our Faith, for we cannot share what we do not have.
The little sheep remind us, too, that Jesus came to go after the lost sheep, for sheep easily become distracted and wander for what seems to be greener pastures. At Christmastime especially, we ought to pray for the lost sheep in our own families and look for the graced opportunities to encourage them to return to the flock.
Then there were the ox and the donkey, two traditional parts of our nativity scene. We read in Isaiah that “the ox knows its owner, and the donkey its master’s crib” (1:3). This prophecy foretold the new people of God, the Church consisting of both Jews and Gentiles. Also, the ox reminds us of what Jesus said: that we must take his yoke upon your shoulders and learn from him, and that in doing so our souls will find rest, for his yoke is easy and his burden light (see Mt 11:29–30). The yoke was custom made to fit a particular ox, and a pair of oxen were harnessed together for plowing. The ox reminds us that we are called to do his work, but that he will help us along the way.
The donkey was the beast of burden that carried our blessed Mother to Bethlehem and carried Jesus into Jerusalem on Palm Sunday. A tradition is that the donkey of Palm Sunday followed Jesus to Calvary. As he hung upon the cross, the donkey bowed down. The shadow of the cross left a dark streak from ear to ear and down the back of the donkey, a reminder that Jesus said that we must, each of us, take up our cross and follow him (see Mt 16:24). The ox and the donkey remind us that we are called to serve the Lord and to serve him in others, alleviating the burden of our fellow man, knowing that we are not alone but that he is always with us.