One unified nature, truly God and truly man.
This is contrary both to the historical understanding and profession of the Church, as well as the mode of expression found within Scripture itself, which ascribes to Christ both deity (John 1:1-3, Titus 2:13, Hebrews 1:13) and humanity (Acts 17:31, 1 Corinthians 15:21-22),
yet does not confound the two natures, such that a new, composite nature is the result. A proof of this is how our Lord is referred to as both the
Son of God (Matthew 16:16, John 1:49, John 11:27, Acts 8:37) and the
Son of Man (Mark 2:27-28, Luke 18:8, John 9:35), the two epithets being employed to draw our attention to a particular facet of Christ's person and work, the former conveying His origin as the eternally begotten Son, who is very God of very God, and the latter being a direct allusion to the Messiah of Old Testament prophecy (Daniel 7:13-14), whom He explicitly identifies with Himself. Note that these
two different natures, humanity and divinity,
subsist in the same person, yet without mixture or confusion, each doing what is proper in itself. The closeness of this conjoining of two natures in the person of the Mediator is such that, in many instances, the properties of one nature are so predicated as properly belonging to the whole person, per Acts 20:28, that they seem to confound the difference between natures. Yet we see in Paul's comparison and contrasting of Jesus with Adam in Romans 5:12-21 and in 1 Corinthians 15:45-49 that he acknowledges an
abiding distinction between the two natures, such that they are recognized
as separate yet indivisibly united in the person of Christ.
As regards to your difficulty concerning the impeccability of Christ and the apparent contradiction of Him undergoing 'temptation' if there was no grounds for the possibility of failure on His part, I advert to the book of Hebrews, as
@MW has before. The humiliation that the Son of God condescended to undergo in His incarnation and earthly sojourn was such as would make Him fit for the office of priest and intercessor, as it is written:
"Therefore, since the children have partaken of blood and of flesh, He also likewise took part in the same things, so that through
His death He might destroy the
one holding the power of death, that is, the devil, and might set free those who all
their time to live were subject to slavery through fear of death. For surely He helps not
the angels, but He helps
the seed of Abraham. Therefore it behooved
Him to be made like the brothers in all things, so that He might become a merciful and faithful high priest
in things relating to God, in order to make propitiation for the sins of the people. For in that He Himself has suffered, having been tempted, He is able to help those being tempted." Hebrews 2:14-18
So then, to repeat verbatim what I said in another thread, "When considering the hypostatic union, then, we may rightly say that the human nature of Jesus was sourced from his mother (Galatians 4:4), but was preserved from the corruption of sin due to the consecrating power of the Holy Spirit in His conception (Luke 1:35). As such, He was akin to a pre-lapsarian Adam in that He was, speaking strictly of his capacities as a man, both able to sin (posse peccare) and able not to sin (posse non peccare). Nevertheless, when we recall that Jesus is Immanuel, the incarnate God with us, and therefore heir to all the attributes of deity that are ascribed to the Father (ala John 14:9 and Hebrews 1:3), then we are forced to recognize his impeccability. As theanthropos, with the divine nature subsisting alongside and upholding the human nature, Jesus Christ was, in a real sense, incapable of committing sin. Yet we acknowledge and confess that He was tempted and tried in all of the ways that we are, yet no sin was found in Him. It is a mystery that is received only in faith, and that even the saints ponder in awe and majesty (1 Timothy 3:16)."
**Edit**
I composed this before realizing that Ben had been banned from the board. Nevertheless, I feel that such a post may yet serve as a nice rejoinder to the arguments that have been adduced against the orthodox doctrine of Christology, particularly the hypostatic union, and its firm basis in the Scriptures, so I'll keep it available for viewing as a matter of public record. May the saints continue to be nourished and built up in the true faith, and let this incident serve as warning for what reductionist Biblicism tends towards.
