“Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit…” Matthew 28:19
Trinity Sunday is the day that the Church honors the most fundamental of Christian beliefs, the Blessed Trinity. On that day, we honour the eternal God: the Father, the Son, and the Holy Spirit: three distinct Persons in one God. The celebration lasts only one day, which is symbolic of the unity of the Trinity.
The Trinity is a mystery; it is beyond the grasp of the human intellect. St. Patrick used a shamrock leaf to symbolize the Trinity for the early Irish Christians; it is one leaf with three distinct but equal parts.
There are other comparisons which catechists use, all perhaps helpful, but woefully inadequate. Water is one substance, but it exists in three forms: as a liquid, as a gas (steam) and as a solid (ice). Three harmonizing notes played together on a piano produce one distinct sound. One person may have three distinct roles: a father, a husband and an employee. These are only inept human efforts to explain the mystery of the Blessed Trinity.
The Church has been celebrating the Trinity in its life and worship since its earliest days. However, in the fourth century, a heresy arose, Arianism, which denied the unity and
equality of the Father, Son and Holy Spirit.
To counter this heresy, Fathers of the Church, like Saint Gregory the Great, dedicated many hymns and Mass prayers to the Holy Trinity and tried to give more importance to this doctrine. Many parishes began to have their own celebrations of the Holy Trinity, but it was not until 1911 that Pope Pius X established Trinity Sunday as a formal feast day.
Each Person of the Blessed Trinity is ascribed a different role in the plan of salvation: the Father is honored as Creator, God the Son, Jesus, as the Savior, and God the Holy Spirit as Sanctifier.
The first Biblical period, from Creation to the birth of Jesus, is considered by some to be the age of God the Father. The Old Testament Jewish people were unsophisticated and rebellious; hence the stern tone of the Ten Commandments.
From the birth of Jesus until the coming of the Holy Spirit on Pentecost may be viewed as the age of God the Son. To the more advanced people of His day, Jesus gave the Beatitudes, guides to behavior which would not only avoid sin, but be pleasing to God.
Humanity is presently in the age of the Holy Spirit. The Spirit is given to each Christian in Baptism and inspires each one to carry on God’s work in the world. Only God knows how long the age of the Spirit will last.
“For you yourselves know very well that the day of the Lord will come just like a thief in the night.” 1 Thessalonians 5: 2
The mission of Christians during this age is to obey the promptings of the Spirit, Who guides us to carry out God’s will here on earth. If we do our job well, we will be rewarded at the end of life’s journey, by seeing the Trinity: Father, Son and Holy Spirit, face to face, in our eternal home in heaven.