The Solemnity of the Most Holy Trinity

"You see the revolving circle of the glory moving from Like to Like. The Son is glorified by the Spirit; the Father is glorified by the Son; again the Son has His glory from the Father; and the Only-begotten thus becomes the glory of the Spirit. For with what shall the Father be glorified, but with the true glory of the Son: and with what again shall the Son be glorified, but with the majesty of the Spirit? In like manner, again, Faith completes the circle, and glorifies the Son by means of the Spirit, and the Father by means of the Son" (St. Gregory of Nyssa).

Today is the Solemnity of the Most Holy Trinity, where we recall the most fundamental mystery of the Christian faith - that God is a Triune God. There is but One Almighty God as Our Lord declared to Moses on Mount Sinai. Yet, in the New Testament we realize the true nature of Our God - He is three persons. For God the Father, God the Son, and God the Holy Spirit are but the same God merely in three different persons. The Holy Trinity can be observed in the Gospel through the words of our Lord: "Go and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost" (Matthew 28:18).

History of the Feast of the Most Holy Trinity

The feast of the Blessed Trinity was first introduced in the 9th century and was only made part of the general calendar of the Church in the 14th century by Pope John XXII. The SSPX website notes:

For the first thousand years of Christianity, no special feast was selected to celebrate this mystery since, as Pope Alexander II (1073) declared, every day of the liturgical year was devoted to the honor and adoration of the Holy Trinity.

It was to counteract the Arian heresy, which denied the fullness of divinity to the Son, that a special text of the Mass in honor of the Holy Trinity was introduced in the liturgical books. It was left to the devotion of each priest, pretty much like the present votive Masses. From the 9th century onwards, bishops of the Frankish kingdoms had a special celebration of the mystery, usually on the Sunday after Pentecost, using a Mass text from Charlemagne's advisor, Abbot Alcuin from 804.

But it was not until John XXII that it was inserted in the official calendar of the Western Church in 1334. However, it is interesting to note that the beautiful Preface of the Trinity (read throughout all Sundays after Pentecost), dates from the time of St. Gregory the Great. 

As Gregory DiPippo of the New Liturgical Movement relates, "There is a minority tradition, which was kept up in the Low Countries and some parts of Germany until the later part of the 16th century, that kept the octave day of Pentecost as a true octave and put Trinity on the Monday after, but that was never done at Rome. From the time it was adopted at Rome, it was always on the Sunday after Pentecost."

Today on the Feast of the Most Holy Trinity, the Athanasian Creed is prayed in the 1961 Divine Office during Prime. Before the changes to the Office in 1955/1956, the rubrics in place under Divinu Afflatu promulgated by St. Pius X were in force. And per those rubrics, the Athanasian Creed was said on all Sundays after Epiphany and Sundays after Pentecost which did not fall within Octaves or on which a feast of a rank of Double or higher was celebrated or commemorated, in addition to being prayed on Trinity Sunday. Thus even Traditional priests who say the 1961 Breviary, will only pray this Creed once a year, on this Sunday.

Truths of the Holy Trinity

1. The Trinity is one. There are three persons but only one God. Each person is God wholly and entirely.
2. Each person is different the other two. The Father, Son, and Holy Spirit are not different roles of the same person. Each person has a different origin.
3. The Father, Son, and Holy Spirit all share one nature. They are related but not the same person while each of them is fully God.

Roles of Each Person of the Trinity

1. The Father sent His only Son: "When the appointed time came, God sent his Son." (Gal. 4:4) also John 8:42
2. The Son came to die our death and free us
3. The Holy Spirit as one who proceeds from the Father and the Son

Addressing Trinitarian Heresies

Since the beginning, many lies and heresies have sprouted as Our Lord warned that many antichrists would come. Some heretics taught Jesus was not God, there were 3 gods, and the 3 persons were just three different roles of the same person. All of these lies and heresies were condemned.

While the Father, Son, and Holy Spirit are each God, the three persons each have a separate purpose in relation to the salvation of the World. However, all the Divine Persons of the Trinity act in perfect unity since God is one and has but one purpose.

While all of this is certainly confusing, we can only pray that through the Holy Spirit's inspiration, we can hope to understand the Trinity. In time we can understand the Trinity and the nature of Our One God better, but only in Heaven will we truly experience the joy of serving the One God and seeing the mystery of the Holy Trinity face to face.

After this brief recap of the truths of the Holy Trinity, let’s briefly identify six key heresies against the Trinity. Some of these same errors still come up, so study this carefully in order to refute them when you encounter them. Click here to learn more.