On this Sunday, we celebrate the feast of the Most Holy Trinity. The word “Trinity” does not appear in the bible, and yet we know that our God is One God in three divine persons – Father, Son and Spirit. They are somehow separate and at the same time indivisible – a true mystery of our faith.
As I pondered the readings and the feast, I began to wonder about the sign of the cross that we, as Catholics, use to begin and end almost every prayer we say. We use it as a sign of faith and reverence whenever we pass a tabernacle, chapel or Catholic church where we believe Jesus is physically present in the Eucharist. We use it to remind ourselves of our baptism when the sign of the cross was made over us and we were claimed for Christ. We use it as a sign of our acceptance of our own crosses. Christ tells us that we must pick up our cross and follow him. The sign of the cross is a representation of our uniting our own sufferings and sacrifices to Jesus’ supreme sacrifice. We also use it to protect ourselves from evil. The early Church Fathers encouraged the sign of the cross in defense against the devil. You are showing the devil that you belong to Christ and that he is your protection.
I wondered when and where this practice began. This is what I was able to find:
The sign of the cross is a very ancient practice and prayer. We don’t have any indication of it in Scripture, but St. Basil in the fourth century said that we learned the sign from the time of the apostles and that it was administered in baptisms. Some scholars interpret St. Paul’s saying that he bears the marks of Christ on his body, in Galatians 6:17, as his referring to the sign of the cross.
When you make the sign, you are professing a mini version of the creed — you are professing your belief in the Father, and in the Son and in the Holy Spirit.
Bert Ghezzi, Catholic Online, “Significance of the Sign of the Cross,” 11/24/2004