It was a birth like no other, but not because it took place far from home, in the section of the building partitioned off for sheltering the animals. Not because the mother was a young Jewish girl, probably still in her teens, her anxious husband hovering around, helpless as she laboured. Not even because the couple were each descendants of the great King David, for at this time Bethlehem was flooded with their relatives. This was a birth like no other because it was the beginning of the living, breathing existence of a human being like no other. Yehoshua ben Yosef was a fully human baby, who (contrary to the popular children’s carol) would have bawled his little lungs out on greeting the world until finding comfort at last at his young mother’s breast. But little Yehoshua was also more than human, he was Christ the LORD. Immanuel, God with us. Conceived miraculously nine months previously, he was not fathered by the godly Galilean carpenter who rejoiced at his first breaths. “Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is from the Holy Spirit,” the angel had told him. “She will bear a son, and you shall call his name Jesus, for he will save his people from their sins” (Matt 1:20–21). Even as Yosef and Mariam held the Son of God and wondered over the event, out on the hills angels were announcing his birth, proclaiming him to be Saviour, Christ the LORD (Luke 2:11).
Mainstream Christians understand the conception of Jesus Christ to be a work of the Holy Spirit, the incarnation of the preexistent Son of God. Jehovah’s witnesses, like their Arian predecessors, understand the Son to have been the first and greatest of God’s creations, who took human form in the womb of Mary; he pre-existed his birth, yes, but not eternally. There was, as Arius said, “a time when he was not.”
Christadelphians believe that Jesus was born of the virgin Mary by the miraculous intervention of the Holy Spirit, and that God was his Father and Mary his mother, and that this was his beginning. “(We) really do believe that Jesus was, and is, literally the Son of God. (We) are not Unitarians, who think of Jesus as just a very superior man; nor are (we) “adoptionists,” holding that God “adopted” Jesus as His spiritual Son. (We) believe that Jesus was God’s “only begotten Son” in the way the scriptures describe.  “He was human as to the substance of which he was made; but divine as to the source from which he came; the Spirit from which he derived his wisdom; and the pattern of the character which he possessed.”
The role of Christ as Creator counters the idea that Jesus was merely a creature and solely human; this has been discussed in Created by Him and for Him. The various “adoptionist” views will be discussed on another occasion. This week I’d like to focus on Bible teaching about the pre-existence of the Son prior to his conception and birth. Mainstream Christians believe that the Son co-existed eternally with the Father and the Holy Spirit prior to the incarnation (“incarnation” comes from the Latin carne, flesh). A new person did begin existence at the conception of Jesus Christ; he was the eternal Word made flesh, which had never happened before. Theologian Millard Erickson explains that “the heavenly Second Person of the Trinity antedated the earthly Jesus of Nazareth. In fact, there was no such being as the earthly Jesus of Nazareth prior to the moment he was conceived in the womb of the Virgin Mary.” 
So it’s not sufficient to try to refute the doctrine of the Son’s prior existence by pointing to the conception of the man Jesus as a starting point in time as if that precludes the prior existence of him who took on flesh and dwelt among us as that man. From the perspective of Old Testament prophecies, the event was future, just as Jesus’ death and resurrection and second coming were future (Gen 3:15; 2 Sam 7:14; Isa 7:14; Mal 3:1 for example). But the One who was to come was also “the same yesterday, today and forever” (Heb 13:8) and “the Alpha and Omega… who is and who was and who is to come, the Almighty” (Rev 1:8;22:13). God says of the Son, “Your throne, O God, is forever and ever, the scepter of uprightness is the scepter of your kingdom…. You, Lord, laid the foundation of the earth in the beginning, and the heavens are the work of your hands; they will perish, but you remain… you are the same, and your years will have no end” (Heb 1:8–12).
Paul says of Christ, “For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities — all things were created through him and for him. And he is before all things, and in him all things hold together” (Col 1:16–17).
Christ’s work was foreordained in the eternal counsels of the Godhead, before the point in time when it became reality. “Concerning this salvation, the prophets who prophesied about the grace that was to be yours searched and inquired carefully, inquiring what person or time the Spirit of Christ in them was indicating when he predicted the sufferings of Christ and the subsequent glories… He was foreknown before the foundation of the world but was made manifest in the last times for the sake of you” (1 Pet 1:11–12, 20). This sure word of prophecy would not fail. The Word, who was God and was in the beginning with God, became flesh in the first century AD and dwelt among us and we have seen HIS glory as of the only Son from the Father (John 1:1–2, 14). Galatians 4:4 states that God sent forth his Son, born of woman, when the fullness of the time was come. “He (God) was manifested in the flesh, vindicated by the Spirit, seen by angels, proclaimed among the nations, believed on in the world, taken up in glory” (1 Tim 3:16) — the same “he” appeared incarnate, was present and active in the world and ascended to heaven.
The Christadelphian response is that Christ did not literally pre-exist physically before his conception, but existed only in the mind and purpose of God, and this is entirely what is meant by these passages. Christadelphian writer Harry Tennant explains their position:
“Everything about Jesus was already planned in the mind of God long before his birth of Mary. This knowledge and purpose preexisted: it had first to be in God’s mind for it to have been prophesied in the Old Testament and for God to have brought it about… From the foundation of the world God knew the Lord Jesus Christ and those who would come to believe in him; he knew the names which would be found inscribed in the Lamb’s book of life at the day of judgement; He had already prepared the kingdom which they would inherit; and had fully ordained all that Christ would do. All these were really there in the mind of God, though none of them actually existed at that time… ‘God calleth those things which be not as though they were’ (Rom 4:17).” 
Reference is made to other passages about the foreknowledge of God concerning events such as Jeremiah’s birth and calling (Jer 1:5) and the certain salvation of those foreordained “before the foundation of the world” (Matt 25:34; Rom 8:29; Eph 1:3–4; Rev 13:8). These passages certainly refer to God’s foreknowledge and foreordaining and expressly say so. (Interestingly, whilst Christadelphians are happy to understand them literally when arguing against the preexistence of Christ, they are far less ready to interpret them literally as a guarantee of individual salvation).
Because God is timeless, of course he foresaw and foreordained the incarnation, birth, death, resurrection and return of Christ. The issue is, is this really the way we are to understand the very existence of the Son whom Scripture expressly states was with the Father and was sent by him? It seems to be a sleight of hand to use the Scriptures in this way and understand all references to the Son and his eternal relationship to the Father in the context of foreknowledge alone. Where is the justification for this particular hermeneutic? Are we really at liberty to choose which passages we shall interpret literally and which figuratively or metaphorically? There is no hint of foreordaining and mere prediction in Jesus’ self-understanding of his origins, and this above all provides the key to understanding the other preexistence passages literally. Consider the plain meaning of these words spoken by or about Jesus in the gospel of John, whose major focus is to express who Jesus is:
“This is he of whom I (John) said, ‘After me comes a man who is preferred before me, because he was before me.’” (John 1:30)
“No one has ascended to heaven but he who came down from heaven, that is, the Son of Man, who is in heaven.” (John 3:13)
“For I have come down from heaven, not to do my own will, but the will of him who sent me.” (John 6:38)
“What then if you should see the Son of Man ascend where he was before?” (John 6:62)
“I know where I came from and where I am going.” (John 8:14)
“You are from beneath; I am from above. You are of the world; I am not of this world.” (John 8:23)
“I proceeded forth and came from God, nor have I come of myself, but he sent me.” (John 8:42)
“So the Jews said to him, ‘You are not yet fifty years old, and have you seen Abraham?’ Jesus said to them, ‘Truly, truly, I say to you, before Abraham was, I am.’” (John 8:57–58)
“Do you say of him whom the Father consecrated and sent into the world, ‘You are blaspheming,’ because I said, ‘I am the Son of God’?” (John 10:36)
“Jesus, knowing that… he had come from God and was going to God…” (John 13:3)
“I came forth from the Father and have come into the world. Again, I leave the world and go to the Father.” (John 16:28)
“Glorify me together with yourself with the glory which I had with you before the world was.” (John 17:5)
“for you loved me before the foundation of the world.” (John 17:24)
The Scriptural testimony is clear and explicit that the Father sent the Son into the world (John 5:37–38; 7:28–29; 17:8; Rom 8:3; Gal 4:4; 1 John 4:10, 14). The language of this sending does not imply that the Son’s existence began at the point of his conception, but if anything that the Father-Son relationship was already established at the point when, “in the fullness of time,” the sending occurred in the birth from a woman. Though he was rich, with the glory he had with the Father, for our sakes he became poor (John 17:5; 2 Cor 8:9). He did not grasp at the equality he had with God but humbled himself in taking on flesh and blood, the form of a servant (Phil 2:6–7). How great is the love of our God, who would do this to save his creation, and invite us to partake of that love which was his and will be throughout eternity! A birth like no other, a life and a death like no other, a love like no other.
1. Jehovah’s witness teaching on the preexistence of Christ may be found at http://www.jw.org/en/publications/books/good-news-from-god/who-is-jesus-christ/
2. Fred Pearce. Jesus: God the Son or Son of God? pamphlet (Birmingham: The Christadelphian, n.d.)
3. Robert Roberts. The Christadelphian Instructor (West Beach SA: Logos Publications, 1985), Articles 43 & 44. Also available at http://www.antipas.org/books/instructor/part1.html
4. Millard Erickson. Christian Theology, 3rd ed. (Grand Rapids: Baker, 2013), 672
5. Harry Tennant. The Christadelphians, What they Believe and Teach (Birmingham: The Christadelphian, 1998), 102–3