Symbols of the O Antiphon include a triangle, which represents wisdom; an adonai, which is a flame that represents the burning bush from which God spoke to Moses; and a root of Jesse, representing Jesus being the son of David who was the son of Jesse. Other symbols include a key to represent Jesus being the key of salvation, a burning sun to represent Jesus as the son of justice and a crown to show that Christ is the king of all man.
The last symbol of the O Antiphons is a manger to represent that Jesus is with man. These symbols are popularly baked as cookies or cut from paper and painted with vegetable coloring to use as decorations on a Christmas tree. The cookies may also serve as decorations, and afterward are still eaten so that people may "taste how God is with them and see how good the Lord looks."
The O Antiphons are verses taken from The Divine Office for the seven days before Christmas. They are a call to Christ to hurry to come again. The O Antiphons are used most often in prayer during the week before Christmas to show the love and desire for Christ.