FULLY GOD, FULLY MAN...the Lord Jesus Christ is Son of God and Son of Man; one Person, two natures

For we do not have a high priest who is unable 

to sympathize with our weaknesses, 

but one who in every respect has been tempted as we are, 

yet without sin. For it was indeed fitting that we should 

have such a high priest, holy, innocent, unstained, separated from sinners, 

and exalted above the heavens. He has no need, like those high priests, 

to offer sacrifices daily, first for his own sins 

and then for those of the people, 

since he did this once for all when he offered up himself. 

-Hebrews 4:15; 7:26-27

The Hypostatic Union is a mystery, but an essential of the Christian faith and foundational truth as to the nature and person of our Lord Jesus Christ. Simply it states that Jesus Christ was fully man and fully God. He had two natures - the human and divine. He did not have a divine humanness nor did He have a humanized divinity. He was both fully man (the human nature) and fully God (the divine nature) in one Person.

As the Council of Chalcedon rightly affirmed in the year 451:

"Therefore, following the holy fathers, we all with one accord teach men to acknowledge one and the same Son, our Lord Jesus Christ, at once complete in Godhead and complete in manhood, truly God and truly man, consisting also of a reasonable soul and body; of one substance with the Father as regards his Godhead, and at the same time of one substance with us as regards his manhood; like us in all respects, apart from sin; as regards his Godhead, begotten of the Father before the ages, but yet as regards his manhood begotten, for us men and for our salvation, of Mary the Virgin, the God-bearer; one and the same Christ, Son, Lord, Only-begotten, recognized in two natures, without confusion, without change, without division, without separation; the distinction of natures being in no way annulled by the union, but rather the characteristics of each nature being preserved and coming together to form one person and subsistence, not as parted or separated into two persons, but one and the same Son and Only-begotten God the Word, Lord Jesus Christ; even as the prophets from earliest times spoke of him, and our Lord Jesus Christ himself taught us, and the creed of the fathers has handed down to us." (emphasis mine)

IOW, we believe that Jesus is verus homus, verus Deus ~ truly man, truly God. At Chalcedon, they went on to set necessary boundaries for how we're to think about the way in which these two natures relate to each other. Importantly, they said "that these two natures are in perfect unity, without mixture, division, confusion, or separation."

To reiterate, when we think about the Incarnation, as Sproul has said, "we don't want to get the two natures mixed up and think that Jesus had a deified human nature or a humanized divine nature. We can distinguish them, but we can't tear them apart because they exist in perfect unity." 

There is the mystery.

This biblically can be found in John 1:1-18. The Word was with God and was God; the Word became flesh; and is the only begotten from the Father. Son of God and Son of Man.

To deny this great truth of His two natures in one Person would be to embrace (even unwittingly) variations of some of the early heresies which spread through the first few centuries of the early church.

One of those heresies is called Ebionism. This heresy is the view that Jesus was in nature just a man, denying his divinity altogether. The Ebionites were an offshoot of the specifically Jewish form of Christianity, which was a potent force in the apostolic age.

Another would be the heresy known as Adoptionism. This heresy is the view that Jesus was in nature a man who became the Son of God by Adoption; that is, that Jesus was virtuous man that God adopted and constituted him as His Son. The earliest extant writing that expresses this view is the Shepherd of Hermas, which is thought to be written by the brother of the bishop of Rome about A.D. 150. It taught that Jesus was an ordinary man, born of Mary and Joseph; at his baptism the Spirit or Christ descended upon Jesus and at his crucifixion the Christ departed, leaving the man Jesus to suffer alone.

Or the heresy known as Docetism. This heresy is the view that Jesus was in nature divine, eliminating his humanity. The name Docetism (Greek, dokein = "to seem") indicated the distinctive thesis of it that Christ's man hood, hence his sufferings, were unreal, phantasmal, appearing only to be human. It claimed that Christ only appeared or seemed to be a man. This view clearly shows the Graeco-Oriental assumption the divine impassability and the inherent evil nature of matter.

Or the most widely known heresy called Arianism. This heresy is the view that Jesus was not fully divine although still related to God as a son to a father. He was created, but not eternal; and made divine but not of the same substance as the Father.

Or the heresy called Apollinarianism. This heresy was the view of Jesus that when the Logos (a perfect divine nature) assumed a human body in Jesus, it took the place of his human mind or soul. This was the view advanced by Apollinaris (c.310-c.390 A.D.), Bishop of Laodicea, in opposition to the doctrine of Arianism. Both views were held to be unorthodox and Apollinarianism was condemned by the Second Ecumenical Council, the First Council of Constantinople in A.D. 381.

Or the heresy of what is known as Nestorianism. It says that Jesus existed as two persons with two distinct natures and denying they existed in unity.

Or to embrace what came to be known as Monophysitism which originated as a reaction to Nestorianism. The Monophysites (led by a man named Eutyches) were horrified by Nestorius’s implication that Christ was two people with two different natures (human and divine). They went to the other extreme, claiming that Christ was one person with only one nature (a fusion of human and divine elements). They are thus known as Monophysites because of their claim that Christ had only one nature (Greek: mono = one; physis = nature).

It is very important and crucial that we get our Christology correct beloved. To reiterate, the biblical and orthodox view is that Jesus was one person with two natures. He was fully human, but yet fully divine in one person (Phil. 2:5-11).

Solus Christus,

Steve
Heb. 1:1-3