(2.25) Sign of the Cross as a Symbol of the Holy Trinity
By the Sign of the Cross, we are also blessing ourselves with the earliest prayer we heard from our birth, to our baptism and in carrying out our day to day activities.
Through the Sign of the Cross, we also proclaim our belief that there is only one God by nature and there are Three Divine Persons in God- the Father, the Son and the Holy Spirit. We already had a glimpse of this mystery at the beginning of time when God said to another:
“Let us make humankind in our image, according to our likeness; and let them have dominion over the fish of the sea, and over the birds of the air, and over the cattle, and over all the wild animals of the earth, and over every creeping thing that creeps upon the earth” (Gen 1:26).
It was furthermore in the Baptism of Jesus that the three divine Persons came together to manifest their presence:
“And when Jesus had been baptized, just as he came up from the water, suddenly the heavens were opened to him and he saw the Spirit of God descending like a dove and alighting on him. And a voice from heaven said, “This is my Son, the Beloved, with whom I am well pleased” (Mt 3:16-17).
In this we believe that "The three Divine Persons, though really distinct from one another, are one and the same God because all have one and the same divine nature” (Baltimore Catechism).
This truth is among many mysteries which we may not be able to fully comprehend due to our human frailties; but we firmly believe this divine revelation because we have God's word for it. We furthermore should pray to Christ so he may grant us knowledge like he did to the Apostle when "he opened their minds to understand the scriptures" (Lk 24:45).