The most profound mystery of the incarnation is the personal oneness of the divine-human Christ. It may be a deeper mystery than the doctrine of the Trinity. The notion of three persons in one nature almost seems less remote from comprehension than the notion of two natures in one person. A core doctrine of the Christian church is:
Jesus Christ is God the Son. Jesus Christ is man. Jesus Christ is one person whose divine and human natures cannot be changed, divided, separated or mixed. Jesus Christ was resurrected bodily from the dead. Jesus Christ was born of a virgin.
- Jesus Christ is God the Son (Isa 7:14 cf Mat 1:23, 44:6; John 1:1-14, 5:18, 10:30, 20:28, 8:58 cf Ex 3:14; Rom 9:5; Phil 2:5-11; Col 1:15-18; Titus 2:13, Heb 1:8; 1 John 5:20; Rev 22:13-18).
- Jesus Christ is man (Mark 2:27,28; John 1:14; Rom 1:3; Phil 2:5-11; 1 Tim 2:5; 1 John 4:1-4).
- Jesus Christ is one person whose divine and human natures cannot be changed, divided, separated or mixed (John 1:14; Rom 1:3,4, 8:3, 9:5; Gal 4:4,5; Phil 2:5-7; 1 Tim 3:16; Heb 2:11-14; 1 John 4:2,3).
- Jesus Christ was resurrected bodily from the dead (Luke 24:36-47; John 2:19-21; Rom 8:11; 1 Cor 15:3-7; 1 John 3:2).
- Jesus Christ was born of a virgin (Isa 7:14; Mat 1:23).
Difficulties encountered in discussing this issue are compounded by the ambiguity associated with certain words. To remove some ambiguity, it is useful to distinguish between two concepts:
- NATURE -- A Complex Composite of Attributes
- PERSON -- A Substantive Entity
The human nature is a complex composite of the human attributes of intellect, will and heart (seat of emotions). These are housed in a substantive entity called a person identified by the body during life and the soul after death. The divine nature is a complex composite of the divine attributes of intellect, will and heart. These divine attributes are transcendent, immanent, infinite, eternal and immutable. They are housed in substantive entities called the three persons of the Trinity: God the Father, God the Son and God the Holy Spirit. The incarnation joined the divine nature of God the Son with the human nature of Jesus Christ, without change, division, separation or mixture, to form a single person who is fully human and fully divine. This implies, for example, that Jesus has both a human will and a divine will which was declared at the third council of Constantinople in 680 AD.
At the instant of incarnation, the divine and human natures of Christ were not changed, divided, separated or mixed. This concept is so foreign to our understanding, that, over the centuries, many well-meaning Christians have tried to fix it! The Eutychians, for example, merged the two natures into a single nature which was neither completely divine nor completely human. (See Section 2.5 of Theology Corner)
Divine and human natures are united in the personal oneness of Christ. In the unity of his personality, He must possess the full attributes of both. As a person, He is not merely God nor merely man but God-man. The divine Son took the nature of man into a personal union with himself. This theanthropic union is permanent. It will never be reversed and there will never be another! It was necessary and sufficient for the substitutionary atonement.