The Gospel of Matthew
NOTES from Lewis Sperry Chafer "The Birth of The King" 
The story of His birth concludes Chapter one, and continues into Chapter two. The virgin birth is here fully revealed and this birth is given as the fulfillment of Isaiah 7:14. The two Gospels, which mention His birth, Matthew and Luke, show in the most perfect way that the Son of God, the eternal Word, became man, born of the virgin, a true human being, yet "that holy thing," absolutely without sin. His human nature proceeded directly from the Spirit of God. The early Jews never attacked the accounts of the birth of our Lord.
I. THE PERSON OF THE KING
A. His Background, 1:1-17
B. His Birth, 1:18-25
Now the birth of Jesus Christ was as follows. After His mother Mary had been betrothed to Joseph, before they came together, she was found in womb to be with child by the Holy Spirit.
"Granting that it was the divine purpose that the Second Person should enter the human realm and become truly man, by what method might He best attain that end? He must have His own identified human spirit, soul, and body; but these would not be secured if He merely took possession of or appropriated some existing human being. That kind of arrangement would result in no more than an indwelling. On the other hand, He would not simply appear among men as one of them without a natural human origin. In such a case His true humanity could never be established nor His rightful relation to the people of the earth. It thus became essential that a member of the Godhead when entering the human family should enter as all others do. By such a procedure no question may be raised about the genuineness of His humanity or the permanency of it. It is true that, because of His unchangeable Deity, He could not be born of a human father. Had He been born of a human father and mother there would have been nothing to identify His humanity as the rightful property of His Deity. On the other hand, had He appeared with no relation to human parentage, there would have been no legitimate basis for the fact of His humanity. The divinely wrought arrangement by which He is generated of the Holy Spirit and born of a woman is the perfect solution of the problem. Raising objections frivolously about whether the mother may impart a complete human nature and perpetuate a racial stock is silenced by the testimony of the Scriptures to the truth that He, though generated by the Holy Spirit, did possess a complete humanity -- spirit, soul, and body. He is of the seed of Abraham, of the tribe of Judah, and the Heir to David's throne. to this body of evidence for His complete humanity may be added the genealogies which trace His human origin back to Abraham and to Adam. This perfect human kinship was demanded if He, as Mediator, undertook the work of redemption. He must be of the Adamic stock with the clearest title and the Fulfiller of the Abrahamic covenant of promise, which covenant stipulates that through Abraham's seed all nations of the earth would be blessed. To the end that this unique Person might sit on David's throne, He must be in the direct line of David and the rightful heir to that throne. Accordingly and in the faithfulness of God, the Second Person in becoming man is born into the Adamic race and became the rightful Fulfiller of the covenants by being born of the stock of Israel, of the seed of Abraham, of the tribe of Judah, and of the kingly line of David (see Chapter End Note No. 1 )."
But Joseph, her husband, because he was a just man, and not wanting to disgrace her, desired to put her away secretly.
Joseph's intentions were those of a loving man. His reaction to Mary's pregnancy was not that of hostility or shame. He wanted to spare her from the gossip and prying eyes of those who would do such things. His intention was to send Mary away privately until the end of her term.
But while he was considering this, behold, and angel of the Lord appeared to him in a dream, saying, "Joseph, son of David, do not be afraid to take Mary your wife home; for that which is in her has been begotten by the Holy Spirit.
This appearance must not be a Christophany. Christophanies are the appearances of the Pre-Incarnate Son of God (Christ before he had His human body). Such as Moses in Exodus 17:6 is told by God, "I will stand before you there on the rock at Horeb; and you shall strike the rock, and water will come out of it, that the people may drink." Or in Genesis Chapter 32:24 ff. here Jacob wrestles with the Angel of the Lord. Imagine, wrestling with Jesus Christ. Christ is the Person of God that may be seen by humans. Neither the Father nor the Spirit can be seen my mere mortals. Only the Son has that ministry and distinction. But here, because Christ, The Son of God, has already entered humanity in bodily form, this must therefore be one of the Arch-angles, and he is identified as Gabriel (Luke 1:31).
"And she will bear a Son; and you shall call Him Jesus, for it is He who will save His people from their sins."
His official name or office is that of Christ, which means "The Anointed One." Here the Messiah and the Christ of the Scriptures meet and identify themselves in the personality of Jesus, who was the Anointed of God as the Prophet, Priest, and King.
The personal name of our Lord was "Jesus", which signifies "Savior." It is carefully accented by repetitions in the record as being highly important. (a) He was called prospectively by Gabriel unto Mary, "...shalt call his name Jesus" (Luke 1:31). (b) He was so named by the angel to Joseph in his supernatural dream, "...thou shalt call his name Jesus, for He shall save His people from their sins" (Matthew 1:21). (c) He was so called on the day of His birth, "...and he called His name Jesus (Matthew 1:25). (d) He was so called when His name was officially bestowed at circumcision, "...His name shall be called Jesus who was so named of an angel before He was conceived in the womb" (Luke 2:21) (see Chapter End Note No. 2 ).
Now all this took place in order that what was spoken by the Lord through the prophet might be fulfilled, saying,
"Behold, the virgin will have, and will bear a Son, and they will call His name Emmanuel (Isaiah 7:14);" which translated means, "God with us."
And Joseph being raised from his sleep, he did as the angel of the Lord commanded him, and took his wife home;
and did not live with her until after she had given birth to a Son; and he called His name Jesus.
Perhaps here is a good place to speak to the issues of "immaculacy." The only issue here that is of deep importance is that no human man had slept with Mary during the time immediately preceding and following the nine month period before the birth of her son Jesus. The concept that Mary was always "immaculate," meaning from birth to her death, has no bearing on any of the issues that touch on the Son of God. The translation of the Greek word "parthenos" or "virgin" is legitimately "a woman who has not had intercourse," but it also has been translated a "a young woman." For the purposes of Christian Faith and Doctrine the importance lies in the FACT that the birth of Jesus Christ was supernatural in nature and that Jesus had no HUMAN father. Mary's virginity, as we would speak of it, either before or after the fact is not relevant to the issue of Virgin Birth. Mary herself said "My soul exalts the Lord, and My spirit has rejoiced in God my Savior." Also see Judges 5:24 and Luke 1:28.
 Lewis Sperry Chafer, D.D., Litt.D., Th.D., Late President and professor of Systematic Theology, Dallas Theological Seminary, "Systematic Theology", Volume V, Christology P.47, 48, Dallas Seminary Press, Dallas Texas