Dear Friends,
This feast is truly and really a mystery. Difficult to explain in words, but, more easily demonstrated by actions.
The Holy Trinity, simply put, is the doctrine of the Church that teaches there is One God, but Three Persons – Father, Son, and Holy Spirit. The Godhead is communal, yet united, that is: One.
Like I said before, talking about this mystery is more easily expressed by action. We make the Sign of the Cross when we bless ourselves, we make the Sign before we eat, we make the Sign at the beginning of Mass, we make the Sign in the celebration of the Sacraments, and we even use the Sign when we pray to the Father, through the Son (Jesus Christ), and driven by the Holy Spirit.
In making the Sign, we celebrate what is an essential Christian teaching. It makes an individual distinctly Christian to use the Sign of the Cross to teach, show, express, and manifest what we believe about God, Jesus, and the Holy Spirit. They are all one God, but, Three Persons. This one God is Creator (the Father), the Redeemer (the Son), and the Sanctifier (the Holy Spirit).
It is difficult to explain, yet, always a doctrine not of explanation, but one of action. God has shown Himself to us, revealed a truth: He is One God – Father, Son, and Holy Spirit!