Nestorius, an unknown heretic to most of us, lived around 300 A.D. to 451 A.D. He denied the unity of the two natures (human and divine) of Christ in the one person of Christ. Nestorius viewed it as two natures and two persons, one human and one divine. This heresy was called Nestorianism.
Nestorius, a presbyter and a monk of Antioch, was a native of the region of Germanica in Syria. The greatest influence upon him was his training in the school of Antioch under Theodore of Mopsuestio. Theodore emphasized the distinction between the human and divine natures of Christ to the point that it resulted in two persons.
Nestorius could not conceive of two natures of Christ without two persons of Christ. He taught that it is not possible for Jesus (Immanuel) to be the person of the eternal Son of God, because he had a beginning in the womb of Mary. Nestorius viewed the second person of the Trinity, who is eternal, to be a divine person; and Immanuel who was born of the virgin Mary, to be a human person, therefore two persons and two natures. He likened the joining of the divine person and the human person in Christ, to the marriage of a husband and wife who remain two distinct persons after the marriage.
How was the divine person united to the human person within Christ? The union was possible only through the mediation of the Holy Spirit. For example, the miracles were not the work of the second person of the Trinity (divine person) but of Jesus the man (human person) through the mediation of the Holy Spirit. If this was true that Jesus was only mere man, we could say that any man could be joined and used by the Holy Spirit. Also, if the Holy Spirit ceased His work of joining the two persons, Jesus as man could go his separate way apart from the second person of the Trinity. By this doctrine, Nestorius denied that Jesus the man was really the person of the Son of God. By denying this, the basis of salvation is destroyed.
God’s Word is very clear that Christ Jesus is very God and very man. We read in Isaiah 9:6, “For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counselor, The mighty God, The everlasting Father, The Prince of Peace.” Also, In Philippians 2:6-8 it reads, “Who being in the form of God, thought it not robbery to be equal with God: But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: And being found in fashion as a man he humbled himself and became obedient unto death, even the death of the cross.”
Even our confessions from early history have taught that Christ is the only begotten Son of God. Belgic Confession Articles 18 and 19 confess that he is very God by his power to conquer death; and very man that he might die for us according to the infirmity of the flesh. We also read in the Heidelberg Catechism, Lord’s Day 5 and 6: By the righteous judgment of God, we deserve eternal punishment for our sins. Since God will not punish any other creature for our sins and we cannot make full satisfaction or sustain the burden of God’s eternal wrath against our sins, we must needs have a mediator. A mediator who is very man to take the sins upon himself and also very God to bear the burden of God’s wrath. Who is this mediator? God’s only begotten Son, our Lord Jesus Christ.
So what must our response be when Jesus is denied as the eternal Son of God, but portrayed as good prophet, man, or an example for to follow? That it is a denial of God’s Holy Word and our confessions, and it destroys the basis of our salvation. We must always be ready to guard and defend against such heresies as Nestorianism.