Introduction
John Cassian lived in the late 4th and early 5th centuries. My first interaction with him came during research for a paper on the Second Council of Orange held in 529 AD. Cassian was one of the first men to crystallize the semi-Pelagian view. A disciple of Augustine, Prosper of Aquitaine, wrote a response to Cassian. Roughly 100 years later, Felix IV, then Pope in Rome referred heavily to Prosper’s response when he edited the initial Canons of the Council of Orange formulated by Caesarius. Thus, until the Council of Trent finally set Prosper and Augustine aside, Cassian’s position on prevenient grace was officially rejected.
Cassian should not, however, be renounced altogether. His defense of the incarnation of Jesus Christ is superb. In this regard, he is entirely orthodox; Nicene even. And, his position on the deity and humanity of the Second Person of the Trinity finds substantial agreement with the Westminster Confession of Faith of the 17th Century. From his Seven Books on the Incarnation of the Lord, Against Nestorius, we will compare his thoughts on Jesus deity, his pre-incarnate existence, and the hypostatic union.
A Characterization of John Cassian’s Era
Cassian depicts heresies of his era as like a hydra – a sea monster of Greek and Roman legend which possessed numerous heads, any one of which would regrow if cut off. Particularly in regard to the incarnate Christ, one heresy would be formulated as an attempt to respond to another. As he noted, “And so one after another out of reaction against heresies they give rise to heresies, and all teach things different from each other, but equally opposed to the faith.”(Cassian 1894, 11:551)
In the 5th Century, Cassian was commissioned by Leo, archdeacon in Rome, to frame a response to the Nestorian heresy. He had recently published his Conferences. It was in this publication that he inveighed against Augustine. Because of this, he expressed some reticence to putting pen to paper again. Thankfully, he overcame his foreboding.
Nestorianism, Including Cassian’s Motive to Write
Nestorianism obtains its name from Nestorius, bishop in Constantinople. The content of the heresy and the man may not be as closely linked as the nomenclature implies. In summary, after Nestorius took the bishopric at Constantinople, his view on a statement about the virgin birth gained notoriety. He preferred to avoid the popular term, in reference to Mary, Theotokos (God-bearer) in favor of christotokos (Christ-bearer) or even theodokos (God-receiving).(Kelly 1990, 316) He held this preference because the popular term sounded very much like the heretical teaching of Apollinarianism. Cyril, bishop of Alexandria, and less-than-fond contemporary of Nestorius, seems broadly to have advertised Nestorius’ preference as a denial of Christ’s deity. In Constantinople his representatives “fostered the opposition there, putting it about that Nestorius disliked the title ‘mother of God’ because he did not believe that Jesus was God.”(Chadwick 1993, 195) Add to this a difficult political environment in Constantinople, and you have a recipe for scandal.[1]
The result of this simmering cauldron of hostility is that our John Cassian was commissioned to offer a response. Knowing that Nestorius had received into fellowship some Pelagian heretics, and prodded by Leo – then archdeacon of Rome – with “commendable earnestness and urgent affection,”(Cassian 1894, 11:550) Cassian consented to do the deed. His offering, in 430 AD, was the Seven Books on the Incarnation of the Lord, Against Nestorius.
It is my opinion that his work rivals that of Athanasius.(Athanasius and Behr 2011) It is well-organized, passionate, terse at times, and thoroughly Scriptural. If Joe Lewis represents the one who denies the deity of Christ, John Cassian is Cassius Clay. Although passionate and curt, his objective always is repentance. In fact, in chapter four of book one, he utilizes the real-life example of a man named Leporius. This man had fallen into the teaching of Pelagius. By God’s grace, Leporius recanted his error. In so doing, he “gave to all the cities of Gaul penitent letters containing his confession and grief; in order that his return to the faith might be made known where his deviation from it had been first published, and that those who had formerly been witnesses of his error might also afterwards be witnesses of his amendment.”(Cassian 1894, 11:553) And, this is Cassian’s hope for any who might identify with the matter of his work.
The Deity of Christ
Book one serves as an introduction. He moves swiftly to state the heresy with which he is dealing, stating,
“[A most poisonous heresy] blasphemously taught that our Lord Jesus Christ was born as a mere man, and maintained that the fact that He afterwards obtained the glory and power of the Godhead resulted from His human worth and not from His Divine nature; and by this it taught that He had not always His Divinity by the right of His very own Divine nature which belonged to Him, but that He obtained it afterwards as a reward for His labours and sufferings.”
Nestorianism was put forward as a form of adoptionism. This is the teaching that Jesus was born a mere man. Because he lived a righteous life he was adopted as the Son of God by God the Father at his baptism. After his resurrection, he was received into heaven as deity. Again, it seems clear that Nestorius himself did not teach this. Nonetheless, this is the opponent against whom Cassian spars.
Let me move to introduce the teaching of the Westminster Standards on the person of Jesus Christ. Chapter eight of the confession provides instruction on Christ the mediator. In paragraph two it states that the “Son of God, the second person of the Trinity…was conceived by the power of the Holy Spirit in the womb of the virgin Mary and of her substance.”[2] Thus he “is truly God and truly man, yet one Christ, the only mediator between God and man.” This statement is not derived from a single portion of Scripture with a neat formula on incarnation. It is derived from the testimony of many Scriptures gathered together and compared. We gain a fuller understanding of many of the mysteries of Scripture by this means we call “good and necessary consequence.”[3]
John Cassian uses this method of compiling the testimony of Scripture very well. Most of the seven books are dedicated to the topic of the deity of Christ. He offers many well-reasoned and exegetical explanations for the faith of the Church in the deity of the incarnate Christ. These cannot all be covered here so I will highlight his argument for the Immaculate Conception, Peter’s confession, and Jesus’ baptism.
To discuss the virgin birth, Cassian drives right at the descriptor with which Nestorius took issue, Theotocos. His response is based on 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.’”[4] From this passage, he argues that Mary’s conception was supernatural, not ordinary. If it was ordinary it would not have required such incredible oversight. It would not have been a significant event. So he asks the obvious question, “If only a mere man was to be born of a pure virgin why should there be such careful mention of the Divine Advent? Why such intervention of Divinity itself?”(Cassian 1894, 11:556) But Christ was not a mere man, even at the conception. The evidence of that is the extraordinary way by which Mary conceived: under the overshadowing of God Almighty. In light of this evidence, he asks, “What room is there for doubt, you incredulous person? The prophet said that a virgin should conceive: a virgin has conceived: that a Son should be born: a Son has been born: that He should be called God: He is called God.” The testimony from Luke and the Old Testament prophets is for John Cassian ample confirmation that Mary conceived and gave birth to the very Son of God. In this Scriptural sense she was in fact the mother of God.
Peter’s confession to Christ in Caesarea Philippi is another portion of Scripture reviewed by Cassian. To confirm the deity of Christ he examines the content of the confession and of Jesus’ response to it. In Matthew 16:16, Peter confesses to Jesus, “You are the Christ, the Son of the living God.” Cassian sees this as a significant challenge to the Nestorian. First, Peter is the “chief of Apostles.”(Cassian 1894, 11:570) Thus, this testimony has a great weight. Second, the confession is strengthened by Jesus response to it. “If you do not like to use the testimony of the Apostle,” he wrote, “use that of God. For by commending what was said God added his own authority to the Apostle’s utterance, so that although the utterance came from the lips of the Apostle, yet God who approved of it made it his own.”(Cassian 1894, 11:570) Jesus did not reject Peter’s testimony. He strengthened it. Thus, anyone who denies the content of the confession must answer to this two-fold authority. The denier must “see how you are taught by the spirit of the devil if you can deny it.”(Cassian 1894, 11:570)
“What do you say now, you heretic?”(Cassian 1894, 11:572) This is how Cassian subtly crescendos his series of arguments for deity. He moves to Jesus’ baptism to offer what he calls a sign for an evil and adulterous generation. For him, the scene in Matthew 3:16 is the clearest of all significations. “After being baptized, Jesus came up immediately from the water; and behold, the heavens were opened, and he saw the Spirit of God descending as a dove and lighting on Him, and behold, a voice out of the heavens said, ‘This is My beloved Son, in whom I am well-pleased’” (Matt 3:16-17). What other indication of Christ’s deity could the denier wish to have? In this passage of Scripture we see the incarnate Christ, the Holy Spirit, and the testimony of God the Father. If this depiction is not sufficient on its own to convince the skeptic, Cassian believes nothing will. He provides a summary statement,
“Christ was baptized. Christ went up out of the water. When Christ was baptized the heavens were opened. For Christ’s sake the dove descended upon Christ, the Holy Spirit was present in a bodily form. The Father addressed Christ. If you venture to deny that this was spoken of Christ, the only thing is for you to maintain that Christ was not baptized, that the Spirit did not descend, and that the Father did not speak.”
There is no testimony stronger than that of God the Father. Here he declares that this Christ is God. With this testimony John Cassian and Westminster thoroughly agree.
The Pre-Incarnate Christ
When describing the second person of the Trinity, we must also account for his pre-incarnate being. In two places, the Westminster Confession of Faith provides a concise description. In chapter two he is one of three persons “in the unity of the Godhead…of one substance, power, and eternity…eternally begotten of the Father.`”[5] In chapter eight, he is “truly and eternally God, of one substance and equal with the Father.”[6]
Cassian takes the same view. In Book 4, he wrote, “let us now show that He who was born in the flesh was God even before His Incarnation…who before His birth was only God, and that He who after He had been brought forth by the Virgin in the body was God, was before His birth from the Virgin, God the Word.”(Cassian 1894, 11:573) The Nestorian view challenged that Mary could not have given birth to a being that existed before she did. This defies the limits of reason and experience. But, Cassian goes on to argue that Mary did not only give birth to One who existed before her. She gave birth to the One who created her. “She became the mother of Him who gave her being.”(Cassian 1894, 11:574)
How is such a thing possible? It is possible, Cassian explains, because God is not subjected to the same limitations as men. “It was as simple for God to bring about birth for Himself as for man and as easy for Him to arrange that He Himself should be born of mankind, as that a man should be born.” Echoes of Athanasius can be heard in these words. It seems there are two modes of reasoning which lead men into heresy: seeking to explain divine mysteries in natural terms, and limiting the supernatural power of God. Nestorianism is guilty of the latter in this case.
In Book 6, he adds Paul’s witness from 1 Corinthians 8:6, “Yet for us there is but one God, the Father, from whom are all things and we exist for Him; and one Lord Jesus Christ, by whom are all things, and we exist through Him.” This Christ who was born of the virgin Mary, existed before all worlds so that all things came into being through him. This is the testimony, he adds, of the Nicene Creed where is states that Christ is, ““Very God of Very God; by whom both the worlds were framed and all things were made.”[7]
On this point of doctrine, Cassian remains true to the Scriptures. He describes the second person of the Trinity as one who, like Westminster, was eternally God. It is this eternal Son of God who was conceived by the power of the Holy Ghost in the womb of the virgin Mary.
The Hypostatic Union of Christ
This last section of our comparison is a review of John Cassian’s view of the hypostatic union. Hypostatic union is a phrase used to describe the way in which the divine nature and human nature coincided in the incarnate Christ. Nestorius the man is critiqued here. Though he did not necessarily deny the deity of Christ or his pre-existence, his view of the union of the two natures lacked “a deeper analysis of the substantial unity of the Lord’s Person.”(Kelly 1990, 317)
Westminster describes it as “two whole natures, the divine and the human, perfect and distinct, were inseparably joined together in one person without being changed, mixed, or confused.”[8] The incarnate Christ was 100% divine and 100% human. These two, complete natures were united in the one person. Yet, these two natures are distinct. They are not “changed, mixed, or confused.” Jesus Christ is fully God and fully man.
John Cassian addresses this in three places: Book 4, chapters five and six, and Book 6, chapter 22. In each place he affirms that Christ is not a composite. He is not two persons. He wrote, “Nor will He permit anyone to hold that there is one Person of the Son of man, and another Person of the Son of God. But in all the Holy Scriptures He joins together and as it were incorporates in the Godhead, the Lord’s manhood, so that no one can sever man from God in time, nor God from man at His Passion.”(Cassian 1894, 11:602) And in Book 4, ” But he testifies that the Word of God is the Son of God, and thus means us fully to understand that the only begotten Word of God, and Jesus Christ the Son of God are one and the same Person.”(Cassian 1894, 11:575)
These criticisms deal specifically with the shortcoming of Nestorianism. In Book 1, he decries Arianism and Apollinarianism as well.(Cassian 1894, 11:552) On this doctrine as well, Cassian demonstrates an orthodox faithfulness.
Conclusion
In terms of Christology, John Cassian, based on his Seven Books, is thoroughly biblical. He affirmed the deity of the incarnate Christ from his birth. He taught that Jesus was the eternal God who did existed before Mary and was greater than she. And he took an orthodox view of the union of the two natures of Christ.
These books of John Cassian have a great deal more to commend them. His link between Pelagianism and Nestorianism is very insightful. The ardor with which he combats for a true Christology is encouraging, And, his thorough Biblicism is instructive.
[1] The political atmosphere is noted in both (Kelly 1990, 310) and given more detail in Chadwick, The Early Church.
[2] WCF 8:2
[3] WCF 1:6
[4] Unless otherwise noted, all Scripture citations are from the NASB.
[5] WCF 2:3
[6] WCF 8:2
[7] Nicene Creed, as in (Cassian 1894, 11:602)
[8] WCF 8:2
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