May. 27, 2018



Rank: Double of the I Class


Glory be to thee O Co-equal Trinity, one God-head before all ages, now, and for evermore. From whom are all things; thro’ whom are all things; in whom are all things; to Him be glory for ever.


Prayer (Collect).

O Almighty and everlasting God, who hast granted thy servants, in the confession of the true faith, to acknowledge the glory of an Eternal Trinity, and, in the power of majesty to adore an Unity. We beseech thee that by the strength of this faith, we may be defended from all adversity. Through our Lord Jesus Christ, Thy Son, who liveth and reigneth with Thee, in unity of the Holy Ghost, God, World without end. Amen.


The mystery of the ever-adorable Trinity is the foundation of the Christian religion, and is firmly to be believed and assented to, though incomprehensible to human reason. What the Christian Church teaches us, with regard to this mystery, in a few words, is this: There is only one supreme Eternal God, Creator of heaven and earth, in three divine Persons, the Father, Son and Holy Ghost, really distinct one from the other. For the Father is not the Son, nor the Holy Ghost; nor is the Son the Father, or the Holy Ghost; nor is the Holy Ghost the Father, or the Son. The Father is from no other: The Son was born of the Father from all eternity, and is equal to him in power and majesty, of the same nature and substance: The Holy Ghost proceeds from the Father and Son from all eternity, is equal to them in power and majesty, of the same nature and substance with them. So that the Father, Son, and Holy Ghost are the One, supreme, Eternal Being; and consequently, tho’ the Father be God, the Son be God, and the Holy Ghost be God, they are but One God equally to be praised, adored, and worshiped for ever.

Let us therefore this day beg Almighty God to preserve us in this Faith, and continue to teach us to submit our reason to revelation. Let us offer our prayers for those unhappy men, who, taking their weak reason for the standard of all truth, impiously give the lie to the Almighty, and refuse to believe God, when he himself teaches us (through the Church) what we are to believe concerning him.


The fi’ry sun now rolls away,
Blest Three and One, eternal day,
The beams of light and love impart
To ev’ry cold benighted heart.

In morning and in ev’ning verse,
Thy glorious praises we rehearse;
May we, O God, the same express
Amidst thy saints in happiness.

To God the Father, and the Son,
And Holy Spirit, three in one,
Be endless glory, as before
The world began, so evermore. Amen.

℣. Thou art blessed, O Lord, in the firmament of heaven.
℟. And worthy of praise and glory for ever.


On the day of Pentecost, the Holy Apostles received, as we have seen, the grace of the Holy Ghost. In accordance with the injunction of their divine Master, (St. Matth, xxviii. 19) they will soon start on their mission of teaching all nations, and baptising men in the name of the Holy Trinity. It was but right, then, that the solemnity which is intended to honour the mystery of One God in Three Persons, should immediately follow that of Pentecost, with which it has a mysterious connection. And yet, it was not till after many centuries, that it was inserted in the Cycle of the Liturgical Year, whose completion is the work of successive ages.

Every homage paid to God by the Church's Liturgy has the Holy Trinity as its object. Time, as well as eternity, belongs to the Trinity. The Trinity is the scope of all Religion. Every day, every hour, belongs to It. The Feasts instituted in memory of the mysteries of our Redemption centre in It. The Feasts of the Blessed Virgin and the Saints are but so many means for leading us to the praise of the God who is One in essence, and Three in Persons. The Sunday's Office, in a very special way, gives us, each week, a most explicit expression of adoration and worship of this mystery, which is the foundation of all others, and the source of all grace.

This explains to us, how it was that the Church was so long in instituting a special Feast in honour of the Holy Trinity. The ordinary motive for the institution of Feasts did not exist in this instance. A Feast is the memorial of some fact which, took place at some certain time, and of which it is well to perpetuate the remembrance and influence. How could this be applied to the mystery of the Trinity? It was from all eternity, it was before any created being existed, that God liveth and reigneth, Father, Son, and Holy Ghost. If a Feast in honour of that Mystery were to be instituted, it could only be by the fixing some one day in the Year, whereon the Faithful would assemble for the offering a more than usually solemn tribute of worship to the Mystery of Unity and Trinity in the one same divine Nature.

The idea of such a Feast was first conceived by some of those pious and recollected souls, who are favoured from on high with a sort of presentiment of the things which the Holy Ghost will achieve, at a future period, in the Church. So far back as the 8th Century, the learned monk, Alcuin, had had the happy thought of composing a Mass in honour of the mystery of the blessed Trinity. It would seem that he was prompted to this by the Apostle of Germany, Saint Boniface. That this composition is a beautiful one, no one will doubt that knows, from Alcuin's writings, how full its author was of the spirit of sacred Liturgy; but, after all, it was only a votive Mass, a mere help to private devotion, which no one ever thought would lead to the institution of a Feast. This Mass, however, became a great favourite, and was gradually circulated through the several Churches; for instance, it was approved of for Germany, by the Council of Selingenstadt, held in 1022.

In that 11th Century, however, a Feast properly so called of Holy Trinity had been introduced into one of the Churches of Belgium,—the very same that was to have the honour, later on, of procuring to the Church's Calendar one of the richest of its Solemnities. Stephen, Bishop of Liége, solemnly instituted the Feast of Holy Trinity for his Church, in 920, and had an entire Office composed in honour of the mystery. The Church's law, which now reserves to the Holy See the institution of any new Feast, was not then in existence; and Riquier, Stephen's successor in the See of Liege, kept up what his predecessor had begun.

The Feast became gradually adopted. The Benedictine Order took it up from the very first. We find, for instance, in the early part of the 11th Century, that Berno, the Abbot of Reichnaw, was doing all he could to propagate it. At Cluny, also, the Feast was established at the commencement of the same Century, as we learn from the Ordinarium of that celebrated Monastery, drawn up in 1091, and where we find mention of Holy Trinity day as having been instituted long before.

Under the pontificate of Alexander the Second, who reigned from 1061 to 1073, the Church of Rome, which has frequently sanctioned the usages of particular Churches, by herself adopting them, was led to pass judgment upon this new institution. In one of his Decretals, the Pontiff mentions that the Feast was then kept in many places; but that the Church at Rome had not adopted it, and for this reason,—that, the adorable Trinity is, every day of the year, unceasingly invoked by the repetition of the words: Gloria Patri, et Filio, et Spiritui Sancto; as, likewise, by several other formulas expressive of praise.

Meanwhile, the Feast went on gaining ground, as we gather from the Micrologus; and, in the early part of the 12th Century, we have the learned Abbot Bupert, who may justly be styled a Doctor in liturgical science, explaining the appropriateness of that Feast's institution in these words: “Having celebrated the solemnity of the coming of the Holy Ghost, we, at once, on the Sunday next following, sing the glory of the Holy Trinity; and rightly is this arrangement ordained, for, after the coming of that same Holy Spirit, the faith in, and confession of, the name of Father, Son, and Holy Ghost, immediately began to be preached, and believed, and celebrated in Baptism.”

In England, it was the glorious Martyr, St. Thomas of Canterbury, that, established the Feast of Holy Trinity. He introduced it in his Archdiocese, in the year 1162, in memory of his having been consecrated Bishop on the first Sunday after Pentecost. As regards France, we find a Council of Aries, held in 1260, under the presidency of Archbishop Florentine, solemnly decreeing, in its sixth canon, the Feast of Holy Trinity to be observed with an Octave. The Cistercian Order, which was spread throughout Europe, had ordered it to be celebrated in all its Houses, as far back as the year 1230. Durandus, in his Rationale, gives us grounds for concluding that, during the 13th Century, the majority of the Latin Churches kept this Feast. Of these Churches, there were some that celebrated it, not on the first, but on the last Sunday, after Pentecost; others kept it twice,—once on the Sunday next following the Pentecost Solemnity, and, a second time, on the Sunday immediately preceding Advent.

It was evident, from all this, that the Apostolic See would, finally, give its sanction to a practice, whose universal adoption was being prompted by Christian instinct. John the Twenty-second, who sat in the Chair of St. Peter as early as the year 1334, completed the work by a Decree, wherein the Church of Rome accepted the Feast of Holy Trinity, and extended its observance to all Churches.

As to the motive which induced the Church, led, as she is, in all things, by the Holy Ghost, to fix one special day, in the Year, for the offering a solemn homage to the blessed Trinity, whereas all our adorations, all our acts of thanksgiving, all our petitions, are ever being presented to It,—such motive is to be found in the change which was being introduced, at that period, into the liturgical Calendar. Up to about the year 1000, the Feasts of Saints marked on the general Calendar, and universally kept, were very few. From that time, they began to be more numerous; and there was evidence that their number would go on increasing. The time would come, when the Sunday's Office, which is specially consecrated to the blessed Trinity, must make way for that of the Saints, as often as one of their Feasts occurred on a Sunday. As a sort of compensation for this celebration of the memory of God's Servants on the very day which was sacred to the Holy Trinity, it was considered right, that once, at least, in the course of the Year, a Sunday should be set apart for the exclusive and direct expression of the worship which the Church pays to the great God, who has vouchsafed to reveal himself to mankind in his ineffable Unity and in his eternal Trinity.

The very essence of the Christian Faith consists in the knowledge and adoration of One God in Three Persons. This is the Mystery whence all others flow. Our Faith centres in this as in the master-truth of all it knows in this life, and as the infinite object whose vision is to form our eternal happiness; and yet, we only know it, because it has pleased God to reveal himself thus to our lowly intelligence, which, after all, can never fathom the infinite perfections of that God, who necessarily inhabiteth light inaccessible. (I Tim, vi. 16) Human reason may, of itself, come to the knowledge of the existence of God as Creator of all beings; it may, by its own innate power, form to itself an idea of his perfections by the study of his works; but the knowledge of God's intimate being can only come to us by means of his own gracious revelation.

It was God's good-pleasure to make known to us his essence, in order to bring us into closer union with himself, and to prepare us, in some way, for that face-to-face vision of himself which he intends giving us in eternity: but his revelation is gradual; he takes mankind from brightness unto brightness, fitting it for the full knowledge and adoration of Unity in Trinity, and Trinity in Unity. During the period preceding the Incarnation of the eternal Word, God seems intent on inculcating the idea of his Unity, for polytheism was the infectious error of mankind; and every notion of there being a spiritual and sole cause of all things would have been effaced on earth, had not the infinite goodness of that God watched over its preservation.

Not that the Old Testament Books were altogether silent on the Three Divine Persons, whose ineffable relations are eternal; only, the mysterious passages, which spoke of them, were not understood by the people at large; whereas, in the Christian Church, a child of seven will answer them that ask him, that, in God, the Three Divine Persons have but one and the same nature, but one and the same Divinity. When the Book of Genesis tells us, that God spoke in the plural, and said: Let Us make man to our image and likeness, (Gen, i. 26) the Jew bows down and believes, but he understands not the sacred text; the Christian, on the contrary, who has been enlightened by the complete revelation of God, sees, under this expression, the Three Persons acting together in the formation of Man; the light of Faith develops the great truth to him, and tells him that, within himself, there is a likeness to the blessed Three in One. Power, Understanding, and Will, are three faculties within him, and yet he himself is but one being.

In the Books of Proverbs, Wisdom, and Ecclesiasticus, Solomon speaks, in sublime language, of him who is eternal Wisdom; he tells us, and he uses every variety of grandest expression to tell us, of the divine essence of this Wisdom, and of his being a distinct Person in the Godhead;—but, how few among the people of Israel could see through the veil? Isaias heard the voice of the Seraphim, as they stood around God's throne; he heard them singing, in alternate choirs, and with a joy intense because eternal, this hymn: Holy! Holy! Holy! is the Lord! (Isaias, vi. 3) but who will explain to men this triple Sanctus, of which the echo is heard here below, when we mortals give praise to our Creator? So, again, in the Psalms, and the prophetic Books, a flash of light will break suddenly upon us; a brightness of some mysterious Three will dazzle us; but, it passes away, and obscurity returns seemingly all the more palpable; we have but the sentiment of the divine Unity deeply impressed on our inmost soul, and we adore the Incomprehensible, the Sovereign Being.

The world had to wait for the fulness of time to be completed; and then, God would send, into this world, his Only Son, Begotten of him from all eternity. This his most merciful purpose has been carried out, and the Word made Flesh hath dwelt among us. (St. John, i. 14) By seeing his glory, the glory of the Only Begotten Son of the Father, (St. John, i. 14) we have come to know that, in God, there is Father and Son. The Son's Mission to our earth, by the very revelation it gave us of himself, taught us that God is, eternally, Father, for whatsoever is in God is eternal. But for this merciful revelation, which is an anticipation of the light awaiting us in the next life, our knowledge of God would have been too imperfect. It was fitting, that there should be some proportion, between the light of Faith, and that of the Vision reserved for the future; it was not enough for man to know that God is One.

So that, we now know the Father, from whom comes, as the Apostle tells us, all paternity, even on earth. (Eph, iii. 15) We know him not only as the creative power, which has produced every being outside himself; but, guided as it is by Faith, our soul's eye respectfully penetrates into the very essence of the Godhead, and there beholds the Father begetting a Son like unto himself. But, in order to teach us the Mystery, that Son came down upon our earth. Himself has told us expressly, that no one knoweth the Father, but the Son, and he to whom it shall please the Son to reveal him. (St. Matth, xi. 27) Glory, then, be to the Son, who has vouchsafed to show us the Father! and glory to the Father, whom the Son hath revealed unto us!

The intimate knowledge of God has come to us by the Son, whom the Father, in his love, has given to us. (St. John, iii. 16) And this Son of God, who in order to raise up our minds even to his own Divine Nature, has clad himself, by his Incarnation, with our Human Nature, has taught us that he and his Father are one; (St. John, xvii. 22)— that they are one and the same Essence, in distinction of Persons. One begets; the other is begotten; the One is named Power; the Other, Wisdom, or Intelligence. The Power cannot be without the Intelligence, nor the Intelligence without the Power, in the sovereignly perfect Being: but, both the One, and the Other produce a Third term.

The Son, who had been sent by the Father, had ascended into heaven, with the Human Nature which he had united to himself for all future eternity; and, lo! the Father and the Son send into this world, the Spirit who proceeds from them both. It was a new Gift, and it taught man that the Lord God was in Three Persons. The Spirit, the eternal link of the first Two, is Will, he is Love, in the divine Essence. In God, then, is the fulness of Being, without beginning, without succession, without increase,—for there is nothing which he has not. In these Three eternal terms of his uncreated Substance, is the Act, pure and infinite.

The sacred Liturgy, whose object is the glorification of God and the commemoration of his works, follows, each year, the sublime phases of these manifestations, whereby the Sovereign Lord has made known his whole self to mortals. Under the sombre colours of Advent, we commemorated the period of expectation, during which the radiant Triangle sent forth but few of its rays to mankind. The world, during those four thousand years, was praying heaven for a Liberator, a Messiah; and it was God's own Son that was to be this Liberator, this Messiah. That we might have the full knowledge of the prophecies which foretold him, it was necessary that he himself should actually come:—a Child was born unto us, (Isaias, ix. 6) and then we had the key to the Scriptures. When we adored that Son, we adored also the Father, who sent him to us in the Flesh, and to whom he is consubstantial. This Word of Life, whom we have seen, whom we have heard, whom our hands have handled (I St. John, i. 1) in the Humanity which he deigned to assume, has proved himself to be truly a Person, a Person distinct from the Father, for One sends, and the Other is sent. In this second Divine Person, we have found our Mediator, who has re-united the creation to its Creator; we have found the Redeemer of our sins, the Light of our souls, the Spouse we had so long desired.

Having passed through the mysteries which he himself wrought, we next celebrated the descent of the Holy Spirit, who had been announced as coming to perfect the work of the Son of God. We adored him, and acknowledged him to be distinct from the Father and the Son, who had sent him to us, with the mission of abiding with us. (St. John, xiv. 16) He manifested himself by divine operations which are especially his own, and were the object of his coming. He is the soul of the Church; he keeps her in the truth taught her by the Son. He is the source, the principle, of the sanctification of our souls; and, in them he wishes to make his dwelling. In a word, the mystery of the Trinity has become to us, not only a dogma made known to our mind by Revelation, but, moreover, a practical truth given to us by the unheard of munificence of the Three Divine Persons; the Father, who has adopted us; the Son, whose brethren and joint heirs we are; and the Holy Ghost, who governs us, and dwells within us.

Let us, then, begin this Day, by giving glory to the One God in Three Persons. For this end, we will unite with holy Church, who, in her Office of Prime, recites on this Solemnity, as, also, on every Sunday not taken up by a Feast, the magnificent Symbol, known as the Athanasian Creed. It gives us, in a summary of much majesty and precision, the doctrine of the holy Doctor, Saint Athanasius, regarding the mysteries of the Trinity and Incarnation. It is a psalm or hymn of praise, of confession, and of profound, self-prostrating homage, parallel to the Canticles of the elect in heaven. It appeals to the imagination quite as much as to the intellect. It is the war-song of faith, with which we warn first ourselves, then each other, and then all those who are within its hearing, and the hearing of the Truth, who our God is, and how we must worship Him, and how vast our responsibility will be if we know what to believe, and yet believe not.

It is:
The Psalm that gathers in one glorious lay
All chants that e'er from heaven to earth found way;
Creed of the Saints, and Anthem of the Blest,
And calm-breathed warning of the kindliest love,
That ever heaved a wakeful mother's breast.


Click here, to view the Famous Creed based on the Trinitarian Doctrine, THE ATHANASIAN CREED. It is also focused on Christology. The Latin name of the creed, “Quicunque Vult,” is taken from the opening words, "Whoever wishes". This creed explicitly states the equality of the three persons of the Trinity.


Taken from: The Liturgical Year - Time after Pentecost, Vol. I, Dublin, Edition 1879; and,
The Divine Office for the use of the Laity, Volume II, 1806


Glory be to the Father, and to the Son, and to the Holy Ghost;
as it was in the beginning, is now, and ever shall be, world without end. Amen.