The Church has proclaimed the procession of Son and Holy Spirit from the Father in its creeds going back to the Council of Constantinople in 381 (Denzinger 86). As Fr. Kenneth Baker summarizes,
The Church teaches in this matter that in God there are two internal divine processions. By ‘procession’ is meant to origin of one from another…. [C]reatures proceed from God by external procession, but the Son and the Holy Spirit proceed by an immanent act of the Most Holy Trinity, since they belong to the internal life of God.The Church’s proclamation of this truth, of course, did not stand on a single pronouncement but upon the living tradition of the faith as expressed in its scripture and tradition, and attested to in the liturgy of the Church and the words of the Church Fathers and Doctors. While both processions originate in the Father, they differ in act and relation. While the Son is begotten and proceeds by generation, the Holy Spirit proceeds by spiration. In the developing theology concerning these processions, which both Latin and Greek churches accepted and to which they attested, two different views arose and expressed differing emphases, which were later the seeds of misinterpretation leading to the Photian schism.
The oneness of the Trinity had been long affirmed by the creeds, and the doctrine concerning the procession of the Son had developed during the Christological debates of the fourth century. Specifically, the Nicene-Constantinople Creed states the following concerning the second Person of the Trinity:
[We believe in] one Lord Jesus Christ, the only begotten Son of God, born of the Father before all ages, light of light, true God of true God, begotten not made, consubstantial with the Father, by whom all things were made…. (Denzinger 86, bracketed content added)The Son is unique in His relationship with the Father as the only begotten. Begetting is the procession proper to the Son and is also referred to as generation. St. Thomas describes this unique procession in Summa Theologica as that kind of generation which involves “what proceeds by way of similitude in the same specific nature” (I, 27, 2). While there is generation of a kind in which an effect proceeds from a cause, as Arius took Jesus’ procession to be (ST I, 27, 1), such a procession does not necessarily entail a procession by way of similitude. The Council of Nicea ended speculation along such lines by declaring the Son homoousious or consubstantial with the Father. As such, His procession can only be by way of similitude, as St. Thomas describes in Question 27, Article 2.
This generation of similitude is well attested in scripture. First, there is the literal claim of generation of Jesus in the annunciation narrative of Luke: “And the angel said to her, ‘The Holy Spirit will come upon you, and the power of the Most High will overshadow you; therefore the child to be born will be called holy, the Son of God’” (1:35). In the Gospel according to John, Jesus frequently alludes to His relationship with the Father: “But the testimony which I have is greater than that of John; for the works which the Father has granted me to accomplish, these very works which I am doing, bear me witness that the Father has sent me” (5:36), or again in 8:54: “Jesus answered, "If I glorify myself, my glory is nothing; it is my Father who glorifies me, of whom you say that he is your God.” Finally, perhaps the most oft quoted of all gospel passages speaks directly to Jesus as One Who is sent: “For God so loved the world that he gave his only Son, that whoever believes in him should not perish but have eternal life” (3:14). In the book of Hebrews, the author interprets Psalm 2:7 in light of Christ’s revelation of Himself as Son: “For to what angel did God ever say, ‘Thou art my Son, today I have begotten thee’?” (1:5).
That He proceeds from the Father, then, is clear in revelation. The question, then, becomes how He proceeds. How does His identity as the Word point to the nature of this procession? We understand His procession to be by way of generation as one like the Father of the same essence. In the Gospel According to John, we hear of the Word being with God and also God (1:1). John employs the Greek word λογος (logos), which carries with it more than the mere notion of the spoken word but of word as concept or idea. In On the Trinity, St. Augustine establishes a foundational notion of Son as the knowledge God (as mind) has of Himself: “For the mind cannot love itself, except also it know itself; for how can it love what it does not know?” (9, 3, 3) St. Thomas develops this idea further, noting that the Son proceeds by way of generation: “He proceeds by way of intelligible action, which is a vital operation:—from a conjoined principle (as above described):—by way of similitude, inasmuch as the concept of the intellect is a likeness of the object conceived” (ST I, 27, A2). The Son’s procession, then, is an act of intellect. He is the thought of God in God’s mind, the perfect Imago Dei possessing all that the Father has.
While the Son proceeds by generation, the Holy Spirit does not. There cannot be two different words of God or two distinct intellectual acts of self recognition in the Father. The Holy Spirit’s name alludes to the form of His procession. The word “spirit” comes from Latin spirare, which means to breathe or blow. In Genesis 1:2 is the first image of the Holy Spirit, the ruah (spirit or breath in Hebrew) that “moves over the face of the waters.” He is the Spirit of the Father (Matthew 10:20) and is spoken of in Matthew 28:19 as equal to the Father. In John 15:26, Jesus speaks of the Spirit as being sent by and proceeding from the Father. Yet He is also the Spirit of the Son (Galatians 4:6) and the Spirit of God and Christ (Romans 8:9).
Unlike the Word, an act of intellection by the Father, the Spirit proceeds by way of an act of the will. St. Augustine is first credited with the notion of the Spirit's procession as an act of the Divine Will and also as the Love of God. St. Thomas develops this notion of Spirit as an act of will in Summa Theologica: “Thus the procession of the intellect is by way of similitude, and is called generation, because every generator begets its own like; whereas the procession of the will is not by way of similitude, but rather by way of impulse and movement towards an object” (I, 27, 4). This willful impulse is the intense love between Father and Son, which manifests itself in this third Person of the Trinity.
While the procession of the Son is by generation, the Church teaches that the procession of the Holy Spirit occurs by spiration. Described in scripture as both the Spirit of the Father and of the Son, sent also by Father and Son (John 15:26, 16:7), it follows that the Spirit proceeds from Father and Son, the very point disputed by Photius, as mentioned above. St. Augustine notes the visible sign of this procession in John 20:22: “For that bodily breathing, proceeding from the body with the feeling of bodily touching, was not the substance of the Holy Spirit, but a declaration by a fitting sign, that the Holy Spirit proceeds not only from the Father, but also from the Son” (4, 20, 29). Ott affirms, citing John 16:15, this procession of the Holy Spirit from Father and Son as from a single principle and a single spiration and notes the testimony of both Greek and Latin Fathers, as well the affirmation in various creeds and by synods and councils from the fifth century and up to the Council of Lyons in 1274. While the Latin Fathers preferred the expression “from the Father and the Son,” the Greek Fathers employed a more subordinating expression, “from the Father through the Son.” Yet these two formulations in no way contradict each other but express different theological understandings of the very same operation.
While the question of the Filioque still stands as one of the primary points of disagreement between the Catholic and Orthodox churches, we can see in the writing of the early Church Fathers a clear understanding of two processions: one by generation and the other by spiration. From the testimony of scripture, we can discern the double procession of Spirit from Father and Son (whether expressed in coordination or subordination). From the works of Augustine and St. Thomas, we come to understand the processions as acts of Divine Intellect and Divine Will: two processions, three Persons, One God.
1. Ludwig Ott, Fundamentals of Catholic Dogma, (Rockford, Illinois: Tan Books and Publishers, Inc., 1974), 62–63.
2. Kenneth Baker, Fundamentals of Catholicism (San Francisco: Ignatius, 1983), 90.
3. J. Lebreton, (1910). The Logos. Retrieved October 7, 2011, from The Catholic Encyclopedia: http://www.newadvent.org/cathen/09328a.htm.
4. George Joyce, “The Blessed Trinity,” The Catholic Encyclopedia, 1912, http://www.newadvent.org/cathen/15047a.htm (accessed October 2, 2011).
5. Augustine, “Of Faith and the Creed,” New Advent, Phillip Shaff ed, 1887, http://www.newadvent.org/fathers/1304.htm (accessed October 8, 2011).
6. Ott, 62–64.
Aquinas, Thomas. “Summa Theologica, Prima Pars.” New Advent. 2000. http://www.newadvent.org/summa/1027.htm (accessed October 6, 2011).
Augustine. “Of Faith and the Creed.” New Advent. Edited by Phillip Shaff. 1887. http://www.newadvent.org/fathers/1304.htm (accessed October 8, 2011).
—. “On the Trinity.” New Advent. Edited by Phillip Schaff. 1887. http://www.newadvent.org/fathers/130104.htm (accessed October 7, 2011).
Baker, Kenneth. Fundamentals of Catholicism. San Francisco: Ignatius, 1983.
Denzinger, Henry. The Sources of Catholic Dogma. Fitzwilliam, New Hampshire: Loreto Publications, 1954.
Joyce, George. “The Blessed Trinity.” The Catholic Encyclopedia. 1912. http://www.newadvent.org/cathen/15047a.htm (accessed October 2, 2011).
Lebreton, Jules. “The Logos.” The Catholic Encyclopedia. 1910. http://www.newadvent.org/cathen/09328a.htm (accessed October 7, 2011).
Ott, Ludwig. Fundamentals of Catholic Dogma. Rockford, Illinois: Tan Books and Publishers, Inc., 1974.