What is Nestorianism?
Nestorianism is contrary to the Christian doctrine of the Hypostatic Union. The Hypostatic Union correctly maintains that Christ is fully God and fully man in one indivisible Person; the God-man, Jesus Christ. Christ was vere homo vere deus or truly man and truly God, having two natures in one Person. While Jesus remained fully God (John 8:58) he added humanity (John 1:14) to his divine nature (John 1:1-2). "For in him the whole fullness of deity dwells bodily" (Col 2:9). His two natures are without confusion, without change, without division, and without separation (Chalcedonian Formula). As John Calvin wrote, "For we must put far from us the heresy of Nestorius, who, presuming to dissect rather than distinguish between the two natures, devised a double Christ" (Institutes 2.14.4).
The Apostle Paul teaches, "For there is one God, and there is one mediator between God and men, the man Christ Jesus" (1 Tim 2:5; cf. 1 Cor 8:6; Col 2:9), "there is but one Lord, Jesus Christ"). Note that Paul does not say there "two" mediators, but only "one." Paul also identifies this mediator as "the man" (not men) Jesus Christ. Nestorianism's belief that Christ is two persons is not Biblical.
Despite all the heresies in the early church (among them, Adoptionism, Albigenses, Apollinarianism, Arianism, Docetism, Ebionism, Gnosticism, Kenosis, Marcionism, Modalism, Monarchianism, Monophysitism, Nestorianism, Patripassionism, Pelagianism, Semi-Pelagianism, Socinianism, Subordinationism, and Tritheism, etc.) the Word of God still abides (1 Pet 1:23). Amidst all these assaults against God and his church by numerous false religions, the church has grown stronger, not weaker. In many ways, the church should be thankful for the gift of opposition!
Dr. Joseph R. Nally, Jr., D.D., M.Div. is the Theological Editor at Third Millennium Ministries (Thirdmill).