Of course, the central claim of Christian faith is the resurrection of Jesus from the dead, which is commemorated on Easter. Christianity could never have been formed without the resurrection, although it could have been (and in fact was) formed without much attention to the birth stories of Jesus, which are absent from all the books of the New Testament except two, the gospels of Matthew and Luke.
Yet I begin my inquiry into why Christmas with neither of those gospels, but with the Gospel of John. The Fourth Evangelist begins his Gospel this way:
John 1:1-4, 12-14: 1 In the beginning was the Word, and the Word was with God, and the Word was God. 2 He was in the beginning with God. 3 All things came into being through him, and without him not one thing came into being. What has come into being 4 in him was life, and the life was the light of all people.Christians call the birth Jesus the Incarnation, the being born into flesh of deity. Unlike Judaism, Christians conceive of the deity as a Trinity, three persons united in one godhead: Father, Son and Holy Spirit. (Ever eager to avoid patriarchy and sexism, the "progressives" of the Church today prefer, "Creator, Redeemer, Sustainer, which simultaneously commits two heresies. One, it depersonalizes the Trinity, which consists of persons in relation to one another, to humanity and the cosmos at large, and two, it reduces the godhead to a small collection of role players or functionaries rather that a fullness of the godhead. But that’s all for another post, perhaps.)
12 But to all who received him, who believed in his name, he gave power to become children of God, 13 who were born, not of blood or of the will of the flesh or of the will of man, but of God.
14 And the Word became flesh and lived among us, and we have seen his glory, the glory as of a father’s only son, full of grace and truth.
The theology of the Trinity followed rather than preceded the life of Jesus. Of course, the Jews affirmed the Oneness of God, and the most common translation of the Sh’ma, the traditional call to worship of the Jews, is, "Hear O Israel, the Lord our God, the Lord is One" (Deut. 6:4) Scholars of Jewish theology point out that the Spirit of the Lord is also referred to in unique ways in the Jewish Scriptures and may be understood as referring to a special presence of God with his people, although not really as a separate person of a unified godhead.
It was the resurrection of Christ and his Ascension into the heavens that forced the development of the doctrine of the Trinity, the scope of which is beyond my point here. Suffice it to say that the deity long proclaimed by the Jews, including, of course, Jesus, came to be understood by the Church Fathers (the church’s leaders who followed the apostles) as a unified godhead consisting in three persons.
Christians say that the birth of Jesus is the Incarnation into full human being of the second person of the Trinity, the Son, and so Jesus was God-being-human. Jesus is thus understood by Christians to be a special and unique presence of the deity with humankind and the created order - not the only presence by any means, but a "never before, never after" presence. So Matthew’s Gospel cites the Hebrew prophet Isaiah to call Jesus Emmanuel, meaning "God With Us."
The apostles and the early churches were all Jews before they began following Christ. They retained their Jewish beliefs. In fact, all the apostles were Jews to begin with and remained so until they were martyred, save John, for following Christ.
The most important thing that the Christians brought with them from Judaism was the theology of covenant. The children of Israel who followed Moses out of Egypt, the focal event of Jewish history, made the Covenant of Sinai with God at that mountain, which became was focusing theological statements of Jewish faith.
For the Jews, the sign of their covenants with God (of which Sinai’s is central, but not solitary) is circumcision. For Christians the sign of their covenant is Christian baptism. Christians do not claim to be under Sinai's covenant, but under the New Covenant in Jesus Christ, instituted by Jesus at the Last Supper, now celebrated by churches as the Eucharist, also referred to as Holy Communion or the Lord’s Supper.
The only mention of the new covenant in the Jewish Scriptures is by the prophet Jeremiah, in the 31st chapter of the book bearing his name. Jeremiah’s prophecy of the new covenant begins,
“Behold, days are coming,” declares the Lord, “when I will make a new covenant with the house of Israel and with the house of Judah, not like the covenant which I made with their fathers in the day I took them by the hand to bring them out of the land of Egypt ... .Modern scholars debate whether Jeremiah was referring to a new covenant that would entirely supplant and replace the covenant of Sinai and its related covenants, or renewal/restoration of the historic covenants, which Jeremiah clearly thought had failed. No prophet after Jeremiah picked up on the new covenant, nor did Jeremiah mention it but this once.
At his Last Supper with his disciples, said St. Paul, Jesus "took the cup also, after supper, saying, "This cup is the new covenant in my blood." However, that’s all that Jesus ever said about the new covenant. Jesus never explained the relationship between himself and the shedding of his blood to the new covenant foretold by Jeremiah.
Nonetheless, Jesus himself, and his apostles after his resurrection, saw Jesus as a unique and personal representation of God among human beings. John said that, "The Word became flesh and lived among us. We have seen God’s glory, the glory of the Father’s only Son."
Christians believe that the incarnation of God as human being was the decisive event in human history because the incarnation changed God’s relationship to us and our relationship to God. The incarnation means that human beings can see, hear, and know God in ways never before possible. “Anyone who has seen me has seen the Father,” Jesus told his disciple Philip.
The Incarnation of God in Jesus means that in Christ, God placed himself at the mercy of all the things which we endure. Jesus became tired and hungry. He was dependent on the charity of others for food and shelter. He lost his patience with other people and became angry; the Gospels record both. There is nothing we experience that Jesus did not know. In every way that we are human beings, so was God in Christ. Jesus was Emmanuel, God with us.
In so acknowledging, we recognize the bond that God has established with us, and its revelation in Jesus. God did not stay distant from us, remote and isolated. In Jesus, God chose to live with humanity in the midst of human weakness, confusion, and pain. To become flesh is to know joy, pain, suffering, and loss. It is to love, to grieve, and someday to die. The incarnation binds Jesus to the “everydayness” of human experience.
When someone receives Christ as Christ was sent – the unique embodiment of the eternal God – and when someone believes in the name of Jesus, God makes him a son or her a daughter of God. It takes a second birth to be made a child of God, a birth of the spirit, not of flesh. We are reborn from above. Jesus said, “Flesh gives birth to flesh, but the Spirit gives birth to spirit. You should not be surprised at my saying, ‘You must be born again’”(John 3:6-7).
So we become brothers and sisters of Christ in the family of God. The New Testament book of Hebrews teaches, “Both the one who makes people holy [that’s God] and those who are made holy [that’s you and me] are of the same family. So Jesus is not ashamed to call them brothers and sisters” (Hebrews 2:11). In a way, the Nativity is an adoption ceremony of all humanity as God’s actual children.
This kind of relationship is, I think, somewhat different from the historic Jewish understanding of themselves as "children of Israel," which (Daniel, correct me if I'm wrong) refers to their descendancy from the House of Jacob, whom the Lord renamed Israel. Christians place (or should place ) no importance on physical genealogy; the Christian New Covenant depends not on lineage but on rebirth by the Holy Spirit through the Lordship of Christ. Hence, Jesus said that his real "mother and brothers" are "those who hear God's word and put it into practice."
That is the significance of Christmas for Christians people, and the basis of Christian proclamation of the Gospel of Jesus Christ. The apostles saw the life, work and resurrection of Jesus as a natural continuation of the history and covenant theology of their own people, the Jews, although with a new twist, centered on an historical person whose significance and very identity was a sharp departure from previous figures in Jewish history. For this reason, and others, Christ following did not survive more than a couple of generations within Judaism. A fuller historical inquiry is for another post sometime. Suffice now to say that Christianity at its finest is aware of its daughterhood of Judaism, and at its worst - well our history is sadly self-explanatory of that.