Understanding the Trinity

“The grace of the Lord Jesus Christ and the love of God and the fellowship of the holy Spirit be with all of you” 2 Corinthians 13: 13.

God has revealed himself to be a Trinity, that is, the mystery of One God in three divine Persons: Father, Son and Holy Spirit. The three persons of the Trinity fully possess the one divine nature of God. To use the Baltimore Catechism’s example: A Nature is “What” someone or something is; a Person is “Who” someone is. “The Trinity is one Nature in three Persons. The three Persons, yet distinct from one another, are one and the same God because all have one and the same divine nature” (Baltimore Catechism, No.2, 32). Because each person of the Trinity shares the divine nature of God each are equal to one another. Each person in the Trinity plays a unique role: God the Father is Creator, Jesus the Son is Redeemer, the Holy Spirit is Sanctifier (sent to continue God’s saving work in the world). For this reason “The mystery of the Most Holy Trinity is the central mystery of Christian faith and life. It is the mystery of God in himself. It is therefore the source of all the other mysteries of faith, the light that enlightens them. It is the most fundamental and essential teaching in the ‘hierarchy of truths and faith’” (CCC[1] 234). The Trinity is of fundamental importance and the central element to all Christian belief because through the Trinity God has revealed himself to us. The Trinity is the source of our faith and the hope of our salvation.

What is the Trinity?

  • “By the Blessed Trinity we mean one and the same God in three divine persons” (Baltimore Catechism, No.2, 29), God the Father, God the Son, God the Holy Spirit. “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, No.2, 32). We have one Nature (God) in three Persons (Father, Son and Holy Spirit). Therefore, “We do not confess three Gods, but one God in three persons, the ‘consubstantial[2] Trinity’” (CCC 253).
    • This may seem like a contradiction but it is not, rather it surpasses human understanding but is not irrational. Reason cannot disprove nor prove this doctrine, it is an article of faith revealed by God. “It says that God is one in nature and three in Persons, but it does not say that God is both one Person and three Persons, or one in nature and three natures. That would be a meaningless self-contradiction” (Kreeft, Catholic Christianity, p. 41). The Trinity may be hard to comprehend but it is not illogical.
  • “The Church uses (I) the term ‘substance’ (rendered also at times by ‘essence’ or ‘nature’) to designate the divine being in its unity, (II) the term ‘person’ or ‘hypostasis’[3] to designate the Father, Son, and Holy Spirit in the real distinction among them, and (III) the term ‘relation’ to designate the fact that their distinctions lie in the relationship of each to the other” (CCC 252).
  • “The reason God is a Trinity is because God is love. Love requires twoness, in fact threeness: the lover, the beloved, and the act, or relationship, of love between them. God is Trinity because God is love itself in its completeness” (Kreeft, Catholic Christianity, p.41; see also Baltimore Catechism no.2, 105). This act of love is a total and complete act of self-giving in which nothing is held back between the Father and the Son. So powerful is this act of love that it generates the person of the Holy Spirit.
    • The Trinity, God himself, “is an eternal exchange of love, Father, Son and Holy Spirit, and he has destined us to share in that exchange” (CCC 221).

The Trinity is One

  • “By saying however, ‘in the name,’ not names, it is distinctly declared that in the Trinity there is but one nature and Godhead; for in this place the word is not referred to the Persons, but signifies the divine substance, virtue and power, which, in the Three Person, are one and the same” (CCT[4], II, II, XIII).
    • Note: The doctrine of the Trinity is consistent in keeping with its Judean Monotheistic roots and avoids a plurality of deities. The Trinity necessarily must be one or it would be inconsistent with the religion from which it arose and would have been rejected by the Jewish people as a type of pagan polytheism.
  • Although the Trinity is one, the three divine persons are distinct from one another. As the Fourth Lateran Council put it, “He is not Father who is the Son, nor is the Son he who is the Father, nor is the Holy Spirit he who is the Father or Son” (DS 804).
    • “The divine persons do not share the one divinity among themselves but each of them is God whole and entire” (CCC 253).
  • This distinction is necessary or the Trinity would suffer from a type of split personality disorder. Rather each of the divine persons is relative to each other. Since the Trinity is one, the Godhead is not divided in divinity; rather it is distinct in individuality in the relationship of each person to the other (CCC 255). 
    • “Inseparable in what they are [God], the divine persons are also inseparable in what they do [each possess the fullness of God’s power acting in accordance with one another]. But within the single divine operation each shows forth what is proper to him in the Trinity, especially in the divine missions of the Son’s Incarnation and the gift of the Holy Spirit” (CCC 267). It is in the context of each persons operation, which gives them individuality within the Godhead.

In Relationship to Each Other

  • “In God there is one being, two processions, three persons, four relations, and five notions. The one being or essence is Divinity, belonging equally and undividedly to each of the Three Persons. The two processions are generation, by which the Son proceeds from the Father, and spiration[5], by which the Holy Spirit proceeds from the Father [and the Son]. The three persons are Father, Son, and Holy Spirit. The four relations are paternity, the Father’s relationship to the Son; filiation, the Son’s relationship to the Father; active spiration, the relationship of the Father and the Son to the Holy Spirit; and passive spiration, the relationship of the Holy Spirit to the Father and the Son. The five notions are a) unbegottenness and b) paternity, belonging to the Father alone; c) filiation, belonging to the Son alone; d) active spiration, belonging to the Father and the Son; and e) passive spiration, belonging to the Holy Spirit alone” (The Faith of the Early Fathers, v2. p.20).
    • “The relation Father – Son, as a clear relative opposition, nicely exposes the meaning of divine ‘relation.’ If these two real relations (Father and Son) are to be found in the order of origin of the procession of the Word, however, how does the procession of Love, or the Holy Spirit, involve a relation of origin? In the order of origin of the procession of Love, spirating Love is opposite to Love being spirated. In this relative opposition according to origin, the Holy Spirit is the relation ‘Love being spirated.’ The relation ‘spirating’ is none other than the Father and the Son. This is so because the ‘Father,’ as we have seen, is distinct from the ‘Son’ only as regards the relative opposition begetter-being begotten. It is this relative opposition alone that distinguishes ‘Father’ and ‘Son.’ Thus Father and Son cannot be distinct in a second way. In begetting the Son, the Father bestowed upon him his spirative power. While the real relations in God are four (begetting, begotten, spirating, being spirated), then, only three relations subsist distinctly in the divine Act. Only three relations – paternity, filiations, procession (or being spirated) – are distinct modes of being the one divine Act…In God, what is distinct are the relations, which subsist or exist distinctly in God. Therefore, the Father, Son, and Holy Spirit are celled Persons inasmuch as they subsist distinctly in the one divine Act. Since, the Persons are distinct only in their mutual relations, each Person is the same as the divine Act. The distinction lies solely in the relative order of origin of the processions, but it is a distinction that makes a difference” (Levering, Scripture and Metaphysics, p. 161 – 62).

Objections to the Trinity

Objection 1: “The Father is greater than I” (Jn 14: 28).

Answer: “Rationalist critics lay great stress upon the text: ‘The Father is greater than I [Jn 14: 28]’. They argue that this suffices to establish that the author of the Gospel held subordinationist views, and they expound in this sense certain texts in which the Son declares His dependence on the Father [Jn 5: 19 & 8: 28]. In point of fact the doctrine of the Incarnation involves that, in regard of His Human Nature, the Son should be less than the Father. No argument against Catholic doctrine can, therefore, be drawn from this text. So too, the passages referring to the dependence of the Son upon the Father do but express what is essential to Trinitarian dogma, namely, that the Father is the supreme source from Whom the Divine Nature and perfections flow to the Son” (Catholic Encyclopedia, http://www.newadvent.org/cathen/15047a.htm). It is Christ’s human nature that is subordinate to the divine will of God not his divine nature which remains one with the Father.  

            It should be noted that a subordinate view of the Son to the Father would create a variety of problems. If there is subjectivity between the Son and the Father then the Son does not share in the fullness of the Father’s divinity. Either the Father has created another God, i.e. the Son or the Son is not God at all. Either there is a plurality of Gods, which is illogical, or Christ is diminished to being a mere creature whose very existence is dependent upon the Father’s creative act. Thus Christ is not equal to the Father since he is a created being rather than a begotten being. This realization destroys the very foundations of the Trinity. Pope St. Dionysius summarized the dangers of such a development in his Letter of Dionysius of Rome to Dionysius of Alexandria when he informed his counter part that, “It is blasphemy, then, and not a common one but the worst, to say that [Jesus] is in any way a handiwork [created]. For if He came to be Son, then [there was a time that] He was not…But if the Son came into being, there was a time when these attributes did not exist [the Son and the Spirit as found in the godhead]; and, consequently there was a time when God was without them – which is utterly absurd…Neither, then, may we divide into three godheads the wonderful and divine Unity; nor may we disparage the dignity and exceeding majesty of the Lord by calling Him a work. Rather, we must believe in God, the Father almighty; and in Christ Jesus, is Son: and in the Holy Spirit; and that the Word is united to the God of the Universe. ‘For,’ says He, ‘The Father and I are one [Jn 10:30];’ and ‘I am in the Father, and the Father in me [Jn 14:10].’ Thus both the Divine Trinity and the sacred proclamations of the [Church] will be preserved” (1, 2-3). If Christ is created the entire Trinity collapses; if Christ is God then the Trinity remains.

Objection 2: The Dogma of the Trinity was not defined until the Council of Nicaea in 325 and was thus a product of the council and not of Church history.

Answer: True, the Council of Nicaea defined the Trinity as an article of faith in 325; false, it did not create the name to suit any theological or political agenda. It must be understood that the Church underwent a variety of persecutions during its early stage of development. Councils were few and localized until Constantine united the bishops of the world in 325 at the Council of Nicaea in an effort to define the fundamental teachings of the Church. Controversy over key doctrinal principles relating to the person of Jesus Christ were often at the forefront of debates and even persisted after the council of Nicaea as well. But the orthodox teaching of the Church from the very beginning had always held that Jesus was God, the second person of the Holy Trinity. Discrepancies often arose in an attempt to correctly formulate the hypostatic union of the Incarnate Logos. Amidst the theological growing pains, the Church was never overcome with false doctrines regarding Christ’s divinity or the Trinitarian formula. The notion of the Trinity, developed out of a necessity for explaining the primary mystery of faith, emerged well before the council of Nicaea. The term Trinity, as far as scholarship knows, first appears in the works of St. Theophilus in 180/81 A.D. (To Autolycus II.15). Origen mentions it in The Fundamental Doctrines I, 6, 1 (220 – 230 A.D) and the Commentaries on Romans 5, 8 (post AD 244), while Tertullian uses the Latin phrase trinitas in On Pudicity 21 (AD 220?). The Anti-Pope Novatian wrote an entire treatise called The Trinity ca. AD 235. Cyprian of Carthage, following the example of Origen, invoking the Trinitarian formula for baptism in AD 254/256 in his Letter of Cyprian to Jubaianus, A Bishop in Mauretania 73, 18. St. Dionysius, Pope (reign AD 260 – 268) wrote about the Trinity is the Letter of Dionysius of Rome to Dionysius of Alexandria I. (AD 262) in a well formulated structure which indicated the divinity of Jesus and the unity of the Trinity. St. Gregory the Miracle-Worker does much the same in The Creed (inter. AD 260/270); the list could go on. One further mention, in Against the Arians,22 (AD 357/358) by St. Foebad of Agen, though written after the Council of Nicaea, gives a picture of the development of the Trinitarian dogma when he says “All, however, are one God. The Three are One. This we believe, this we hold, because this we have received from the Prophets, this do the Gospels tells us, this the Apostles handed down, this the martyrs confessed by their suffering. In this we adhere to the faith even with our faculties of mind – against which even if an evil angel of heaven pronounced, let him be anathema” (Courtesy: William A. Jurgens, The Faith of the Early Fathers, v.1. p.391).

            Furthermore the Trinity formula, though not explicitly expressed as “Trinity” can be found within the liturgical framework of the early Church. The greatest weight must be attributed to these liturgical actions, since they do not express the private opinion of a single individual, but the public belief of the whole Church; this is especially true of the baptismal formula. The Church would be mindful to follow the instructions of Christ to baptize in the “name of the Father and of the Son and of the Holy Spirit” (Mt 28: 19); the most explicit mention of the Trinity in scripture. St. Hippolytus (d. 236), referring to the baptismal formula of the Church, states “He who descends into this laver of regeneration with faith forsakes the Evil One and engages himself to Christ, renounces the enemy and confesses that Christ is God . . . he returns from the font a son of God and a coheir of Christ. To Whom with the all holy, the good and life giving Spirit be glory now and always, forever and ever. Amen” (Sermon on Theology, 10). Origen, in the Commentaries on the Romans 5, 8 (post AD 244), said, “For indeed, legitimate Baptism is had only in the name of the Trinity”. This is the practice of the universal Church long before Nicaea and is testimony to the indisputable fact that the notion of the Trinity (see CCC 249).

Citations from the Church Fathers:

  • St. Theophilus: “The three days before the luminaries were created are types of the Trinity (9): God, His Word [Jesus], and His Wisdom [spirit]” (To Autolycus, II.15, AD 180/81).
  • Cyprian of Carthage: “When Christ himself commands the nations to be baptized in the full and united Trinity… ” (Letter of Cyprian to Jubaianus, A Bishop in Mauretania, 73, 18 AD 254/256).
  • Origen: “For indeed, legitimate Baptism is had only in the name of the Trinity” (Commentaries on the Romans, 5, 8, post AD 244).
  • Origen: “For we have indicated in the preceding pages those questions which are bound by clear dogma, which I think I did to the best of my ability when speaking of the Trinity” (The Fundamental Doctrines, I, 6, 1. inter. AD 220 – 230).
  • St. Dionysius, Pope (regn. AD 260 – 268): “It is blasphemy, then, and not a common one but the worst, to say that the Lord is in any way his handiwork [Jesus was created by God the Father]. For if he came to be Son, then once He was not; but if, as He says himself, He be in the Father, and if, which you know the Divine Scriptures says, Christ be Word and Wisdom and Power, and these attributes be powers of God, then He always existed. But if the Son came into being, there was time when these attributes did not exist; and, consequently, there was a time when God was without them – which is utterly absurd…Neither, then, may we divide into three godheads the wonderful and divine Unity; nor may we disparage the dignity and exceeding majesty of the Lord by calling Him a work. Rather, we must believe in God, the Father almighty; and in Christ Jesus, His Son; and in the Holy Spirit; and that the Word is united to the God of the Universe. ‘For,’ says He, ‘the Father and I are one [Jn 10: 30];’ and ‘I am in the Father, and the Father in me [Jn 14: 10].’ Thus both the Divine Trinity and the sacred proclamation of the Monarchy will be preserved” (Letter of Dionysius of Rome to Dionysius of Alexandria, 1, AD 262).
    • Authors Note: The significance of this passage cannot be underestimated. It clearly outlines the orthodox teaching of the Church regarding the Trinity and the uniform equality of the three God heads; Father, Son and Holy Spirit.
  • St. Gregory the Miracle-Worker: “Wherefore there is nothing either created or subservient in the Trinity, nor anything caused to be brought about, as if formerly it did not exist and was afterwards introduced. Wherefore neither was the Son ever lacking to the Father, nor the Spirit to the Son; but without variation and without change, the same Trinity forever” (The Creed, inter. AD 260/270).
  • St. Athanasius: “For the Godhead is one, and there is one God in three Persons” (Incarnation of the Word of God, 10, ca. A.D. 365).
  • St. Athanasius: “But if the Spirit were a creature, He would not have joined Himself with the Father, lest the Trinity be dissimilar within Itself, lest It have united in Itself anything strange or foreign. Indeed, what could be lacking in God, that He should assume any foreign substance, and be glorified with it? Inconceivable!” (Four Letters to Serapion of Thmius, 3, 6, (A.D. 359069).
  • Didymus the Blind: “In the Trinity there is one and the same will” (Against the Manicheans, 3, 12, A.D. 381 – 92).

The Trinity in Scripture

The following is by no means an exhaustive look at every biblical passage that relate to the Trinity. Presented here are some of the clearest examples of the Trinity, and the Three Persons which it consist of, as present in the Canon of Scripture. What can be said for certain is that the various elements of the Trinity are asserted or implied in the context of scripture are to numerous to count.

The Persons of the Trinity in the Bible

  1. There is only one God
    1. Deut 6:4 – “Hear, O Israel! The Lord is our God, the Lord is One!” (In Judaism this is the beginning of the Shema, the basic principle of the whole Mosaic Law.)
  2. That the Father is God
    1. NT: John 5:18,10:30

                                               i.     John 6:46 – “No one has seen the Father except the one who is from God has seen the Father.”

    1. OT: Deuteronomy 32:6, Isaiah 63: 16

                                               i.     Malachi 2:10 – “Have we not all the one Father? Has not the one God created us?”

  1. That the Son is God
    1. NT: John 8:58, 10:30, 10:36, 20:28, Galatians 1:1

                                               i.     Colossians 2:9: “For in Christ all the fullness of the Deity lives in bodily form.”

    1. OT: Psalm 110, Isaiah 9: 1 – 6, Daniel 7: 13 – 14

                                               i.     Psalm 2:7 – “You are My Son, Today I have begotten You.”

  1. That the Holy Spirit is God
    1. NT: Matthew 28:19, 10:20, Luke 24: 29, 1 Corinthians 2:10

                                               i.     Luke 12:12 – “For the Holy Spirit will teach you at that moment what to say.”

    1. OT: Psalm 104:30, 2 Samuel 23:2,

                                               i.     Jon 33:4 – “For the spirit of God has made me, the breath of the Almighty keeps me alive.”

The Trinity Prefigured in the Old Testament

  • Traces of the Trinity are found through the Old Testament and brought to light in the context of the New as revealed by God through His Word Jesus Christ. As Augustine notes, “Just as the one true God is the Creator of both temporal and eternal good things, so too is He the Author of both Testaments, because the New is prefigured in the Old, and the Old is unveiled in the New” (Against Julian, 1, 17, 35).
  • The Trinity is indeed pre-figured in the Old Testament and one of the clearest examples of this in the book of Genesis 1: 26 when the formation of man is described. Frank Sheed in Theology and Sanity points to this when he says that “There are in the Old Testament stray hints and gleams of [the Trinity], but they are no more than that. Thus in the first chapter of Genesis God says (verse 26), ‘Let us make man to our image and likeness’, and in the next verse we read, ‘And God made man to his image and likeness”: the plural words ‘us’ and ‘our’ seem to suggest that there was several persons; the singular word ‘his’ that they were somehow one. I do not mean that the human writer of Genesis knew how apt to the reality of God were the words he wrote: but God who inspired him knew it” (p. 85).
    • Ratzinger makes a similar point when he notes that “There is a ‘We’ in God – the Fathers found it on the very first page of the Bible in the words ‘Let us make man’ (Gen 1: 26); there are an ‘I’ and a ‘You’ in [God]” (Introduction to Christianity, p. 182); thus in the very act of creation there is a foreshadowing of the Trinity. It is also worthy to note that Genesis 1:1 starts with the words “In the beginning” thus indicating the creative act of the Trinity is present from the onset. It should be pointed out that there is an inherent connection to the first line of John’s gospel [“In the beginning was the Word”] contained within the first line of Genesis.  
  • Isaiah 6:8 – “Also I heard the voice of the Lord, saying, Whom shall I send, and who will go for us? Then said I, Here am I; send me” (emphasis added).
  • Genesis 18: 1 – 2 – “The Lord appeared to Abraham by the terebinth of Mamre, as he sat in the entrance of his tent, while the day was growing hot. Looking up, he saw three men standing nearby.” This scene is famously depicted in The Icon of the Old Testament Trinity also known as The Icon of the Holy Trinity by Andrei Rublev.

In the New Testament

Summarizing the role of scripture in the formation of Trinitarian belief from the Old to the New Testament, St. Gregory of Nazianzen argues that the revelation was intentionally gradual: “The Old Testament proclaimed the Father openly, and the Son more obscurely. The New manifested the Son, and suggested the deity of the Spirit. Now the Spirit himself dwells among us, and supplies us with a clearer demonstration of himself. For it was not safe, when the Godhead of the Father was not yet acknowledged, plainly to proclaim the Son; nor when that of the Son was not yet received to burden us further” (Orations, 31.26).

  • Luke 1: 35: “The angel answered and said to her, 'The Holy Spirit will come upon you, and the power of the Most High will overshadow you; and for that reason the holy Child shall be called the Son of God” (Luke 1:35).
    • “What is much weightier is that it is precisely in the scene of the Annunciation that the angel’s threefold speech is the first explicit mention of the three hypostases of the Godhead: ‘The Lord is with you’ (Yahweh, the God of Israel, who Jesus will call his Father); ‘you will bear the Son of the Most High’; [the] ‘Holy Spirit will overshadow you.’ If the Father, as the Almighty, remains on high, if, on the other hand, the Son allows himself to be borne into the womb of the Virgin, thus allowing his Incarnation to occur, rather than actively carrying it out, it is, and always will be, the Holy Spirit, as the third divine hypostasis, who is the real agent in the Church’s prayers and sacraments and charisms” (Balthasar, Mary the Church at the Source, p.154).
  • Matthew 3: 16 – 17: “As soon as Jesus Christ was baptized, he went up out of the water. At that moment heaven was opened, and he saw the Spirit of God descending like a dove and landing on him. And a voice from heaven said, ‘This is my Son, whom I love; with him I am well pleased’” (see also Mark 1: 10 – 11, Luke 3: 22, John 1: 32).
  • Acts 7: 55: “But Stephen, full of the Holy Spirit, looked up to heaven and saw the glory of God, and Jesus standing at the right hand of God.”
  • Matthew 28: 19: “Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit.”
  • 2 Corinthians 13: 14: “The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with all of you.”

In Conclusion

“All, however, are one God. The Three are One. This we believe, this we hold, because this we have received from the Prophets, this do the Gospels tells us, this the Apostles handed down, this the martyrs confessed by their suffering. In this we adhere to the faith” (St. Foebad of Agen,Against the Arians, 22, AD 357/358).




[1] CCC – Catechism of the Catholic Church

[2] The term was coined by Tertullian in Against Hermogenes, 44, in order to translate the Greek word homoousios. The Greek noun ousia means being or substance while the adjective homoousios means of the same substance. Consubstantialis is the Latin translation from homoousios which translated into English is consubstantial. The term describes the relationship between the divine persons of the Trinity as containing the same substance or being as one other (see CCC 252).

[3] Hypostasis means, literally, that which lies beneath as basis or foundation. Hence it came to be used by the Greek philosophers to denote reality as distinguished from appearances (Aristotle, "Mund.", IV, 21).

[4] CCT – Catechism of the Council of Trent

[5] Spiration – A traditional term employed to distinguish the manner in which the Holy Spirit proceeds from the Father (and, according to Western theology, from the Son [Filioque]), and the generation or filiaiton of the Son. The Son is ‘begotten’ from the Father, whereas the Spirit is ‘breathed’ from the Father (and the Son).