On the hypostatic union and nature of Christ, Catholics and Protestants pretty much agree on this definition:
http://www.144000.110mb.com/trinity/index.html#5
The Hypostatic Union: Jesus is fully God and fully man. This God-man is both divine and human, a divine Person who assumed a human nature. [ Top ]
The dual nature of Christ, that he was, and is, God and man, illustrates the Jehovah's Witnesses’ confusion with respect to Christ’s temptation by the devil. The Jehovah's Witnesses incorrectly teach that Trinitarians believe that Jesus was not human and did not have his own human will, stating:
The temptation of Jesus would make sense only if he was, not God, but a separate individual who had his own free will, one who could have been disloyal had he chosen to be, such as an angel or a human. (Should You Believe, Chapter 6)
This is completely false and misleading. First, by virtue of the hypostatic union, Jesus is a divine person with a human nature, God and man, and the man, Jesus, did have his own free will:
Just as there are two complete and perfect natures in Christ, one divine, the other human, there are two wills in Christ, one divine, the other human. (Catholic Encyclopedia, 947)
Trinitarianism teaches that Jesus was not only true God, but true man. “[I]n his body Christ thus expresses humanly the divine ways of the Trinity.”
The Son of God … worked with human hands; he thought with a human mind. He acted with a human will and with a human heart he loved. Born of the Virgin Mary, he was truly been made one of us, like to us in all things except sin. (Catechism of the Catholic Church [New York, Image-Doubleday, 1994], 132) (Catholic Catechism)
Though not infinite, and therefore not omnipotent, because His humanity is finite, [His theandric power] extends to effects that are beyond purely human or created causality. (Catholic Encyclopedia, 943)
It is important that you understand this.
Secondly, and more important, the doctrine of the Trinity teaches that “The humanity of Christ is a creature, it is not God” (ibid., 922). Christ’s full and complete humanity was a necessity, but a humanity that was without sin.
Third, “In Jesus humanity does not exist in itself, but it is the Son who exists as man through his human nature. Jesus gives back his whole divine self to the Father on the cross in and through his humanity (Fundamentals of Christology, 320).
With this in mind, the weaknesses in the Jehovah's Witnesses’ arguments become clear. They falsely teach, implicitly and explicitly, that Trinitarians believe that the humanity of Christ the creature is God the Almighty, the Godhead. But nothing could be further from the truth. When they claim that Trinitarians believe that “Jesus is God” they don’t disclose despite centuries of evidence, that “Jesus” in this Trinitarian context refers to the divine Person who assumed a human nature, not the created humanity of Jesus that is not God.
This particular distortion, and scant reference or explanation of the hypostatic union of Christ the God-man, has enabled the Jehovah's Witnesses to compose pages of unwarranted attacks on the Trinity by taking advantage of the readers’ lack of understanding with regard to what the Trinity doctrine really means.
Fourth, Trinitarians are fully aware that the created humanity of Jesus was inferior to God, that He was not equal to God in every way. The created humanity of Jesus knew that the Father was his superior.
Existence and Nature of Human Will. Moreover, works of honor are attributed to Christ, such as prayer, obedience, merit, which cannot proceed from the divine will, since they are manifested to a superior. They can proceed only from a created will. In His Incarnation the son of God assumed a perfect human nature, at the same time retaining His perfect divine nature. (Catholic Encyclopedia, 948)
Thus, when the created humanity of Jesus prayed to his Father, he was not praying to himself as the Jehovah's Witnesses mistakenly claim. He was praying to the infinitely superior God, His Father.
The Holy Spirit is not considered inferior to the Father and the Son in the way in which the Son, because of the human nature which he has assumed, testifies that he is inferior to the Father and the Holy Spirit (Denz 527)…. (Catholic Encyclopedia, 96)
When you think of it, Christ’s dual nature is not so far fetched; after all, a human is a material being endowed with a spirit, a union of the material and spiritual, yet considered one.
Fifth, with the above in mind, and considering the many proofs that follow, John 1:14 was not meant to be read literally. It states, “And the Word became flesh,” but this does not mean that the Word made a complete transformation from a spirit angel to only flesh, which is a type of heretical modalism condemned by the church in the first centuries. Rather, the divine Person of Christ assumed a human nature. Jesus was a divine Person with a human nature. That is the only acceptable interpretation of John 1:14 because the divinity of Christ - that he was and is God - is an undeniable Biblical truth, and without His divinity redemption is not possible. It was necessary for Jesus to be a God-man for the sake of mankind’s salvation. Therefore He could not be “mere flesh” under any circumstances.
Besides, since “Jesus Christ is the same yesterday, and today, and forever” (Hebrews 13:8 NWT) He cannot have been a preexistent angel who changed completely into mere flesh, and then reverted back to heaven as an angel. There is no such radical change in the Trinitarian Christian world where the Word was God the Son, remained God the Son during His sojourn, and continued as God the Son after His resurrection and ascension.
Sixth, the practical implications of the union is that “Jesus sometimes spoke as man, sometimes as God; sometimes as Godman” (M. O’Carroll, Trinitas: A Theological Encyclopedia of the Holy Trinity [Wilmington, Delaware, Michael Glazier, Inc., 1987], 186) (Trinitas).
6) Further articulation of the Hypostatic Union - the nature of the God-man Jesus. [ Top ]
The divinity of Jesus and his two-fold nature raised numerous questions such as “How a divine Jesus could maintain his full humanity?” Over the years a series of church councils strove to articulate the God-man nature, usually in response to successions of false teachings.
In brief, church councils decreed “that Christ had a true human soul” (Encyclopedia of Religion, 20), in Christ existed “two natures in one person [prosopon] or acting subject [hypostasis] (ibid.). “This personal unity left the divine and human natures quite in tact and in no way confused or intermingled them with each other” (ibid.). Both natures were unaltered and undiminished (Catholic Encyclopedia, 932). Christ not only had two wills “but also two intellects,” one divine, the other human (ibid., 924).
“If the pivotal assertion of the New Testament, “The Word was made flesh” (Jn 1.14), means anything, it signifies that two, the divine and the human, became somehow uniquely one in Jesus of Nazareth; that in Him was achieved a union, elsewhere unparalleled of God with man” (ibid., 918).
The Church believes that Jesus Christ is true God, Son of God made man, the Second person of the Trinity, who took unto Himself a human nature and so exists not only in the divine but also in a human nature: one divine Person in two natures. The man who in His earthly life was known as Jesus of Nazareth was not a human person made one, as Nestorius said, in a unique way of moral unity, with the Person of the Son of God. He was God, Son of the Father, made man for men’s salvation. (ibid., 932)
“His human nature, perfect and complete, was not a human person distinct from the Divine person of the Word … it was the human nature of a Divine Person. This point of our faith enwraps the humanity of Christ in full mystery. … His human life included true human knowledge and a human will distinct from the divine will” (ibid., 936).
Our faith in Christ, the God-man, supposes that his humanity is not a human person (the mystery). For if it were, and if there were a duality of persons in Christ, then the Divine Person would not really be man but only united with a man; Christ would not be what our faith says he is.” (ibid., 937)
“Christ is one Person, that of the Logos, in two complete and integral natures” (Council of Chalcedon in 451) (ibid., 921), but “U]nion of the human nature with the divine self in no way diminishes the human nature” (Constantinople III in 681) (ibid.,). “[T]he human nature of Christ had its foundation in the divine self, the Second person of the Blessed Trinity,” (794 AD, A synod at Frankfurt) (ibid.).
Not only did Christ have two natures, but he had two consciousnesses as well, although some contemporary theologians dispute this and believe Christ had only one conscience.
Christ is a Divine Person simultaneously existing in two natures, divine and human. Because each of the natures is complete in itself, each has its own proper will and intellect. And further, because consciousness is the inescapable concomitant of intellectual activity, it must be conceded that each of Christ’s natures possessed its own proper consciousness, its own proper awareness of self. Christ, therefore, had not one, but two, consciousnesses. (Catholic Encyclopedia, 927)
