Knowing the genealogical tree of one's family was very important in the Old Testament (Numbers 1:18; see 1 Chronicles 4:33; 5:17; 9:1). And this was particularly important among the Shemitic (probably Sumerian) people from whom Abraham was descended (Genesis 11:10-32).
Even the lines of the Arab cousins descended from Abraham are carefully listed (Midianites and other Arabs, Genesis 25:1-4, Ishmaelites, 25:12-18, Edomites, 36:9-43. These Arab tribes were eventually united by Muhammad as children of Ishmael).
The twelve tribes who became the Jewish people were descended from Jacob, who was renamed Israel (Genesis 29:31-30:24; 35:16-18). But it is the genealogy of the messianic the line of David that is recorded with great care (Ruth 4:18-21; 1 Chronicles 2:5-17; 3:1-24).
The reason for this was that David had himself been assured that God had a special purpose for his family, and this is referred to again and again by the prophets (Isaiah 9:7; 11:1, 10; 16:5; Jeremiah 23:5; 33:15-26; Ezekiel 24:23-24; 37:24- 25; Psalm 89:3, 20, 29, 36; Micah 5:2).
In the genealogy of Jesus four women are picked out for special mention by Matthew, and in the commentary we will note how in each case the circumstances are highly unusual (1:3, 5, 6). Many people would have excised such details from their national history, but the Jewish Old Testament is remarkable in never whitewashing the royal line. And it almost seems as if Matthew glories in the Messiah flowering from such foul manure. He also glories in Joseph's faith to accept Mary's son Jesus as his own and give him the legal title to the throne of David.
1:1-2 To highlight the Messiah's Davidic genealogy Matthew begins with "the genealogy of Jesus the Messiah, the son of David" (1:1). Similarly in Luke's Gospel Mary is told that her son "will be called the Son of the Most High, and the Lord God will give him the throne of his ancestor David."
Abraham was given a threefold promise concerning the land, the Abrahamic people, and the blessing of all nations through him. The promises were repeated exactly to Isaac and Jacob (Genesis 12:2-3; 26:3-5; 28:13-14). It seems that Matthew realized that the blessing of all nations could only be through the Messiah. Which is why Matthew will end his Gospel with the purpose to bless the nations through the Messianic apostles in all the world (28:18-20).
1:3-4 Judah, the father of the Messianic tribe, married a Canaanite woman. When his elder son Er died, the second son was expected to father a child for his brother's widow Tamar (as in the question to Jesus, Matthew 22:24). The brother refused to do this, perhaps in case his children's right to the family line was endangered. When Judah refused to make his son do what was required, Tamar dressed herself as a prostitute and tricked her father into fathering Perez who became the ancestor of the Davidic line (Genesis 38:1-29; compare the name Perez in 1:3; Luke 3:33).
1:5 Rahab was the Canaanite prostitute who recognized God's hand in the invading Israelites, and risked her life by welcoming the spies to her home (Joshua 2:1-21; 6:17, 25). She was taken in marriage by Salmon the son of a famous general of the tribe of Judah (Numbers 1:7; 2:3; 10:14), and so gave birth to David's great grandfather (Ruth 4:18-22).
Ruth was the daughter of a Moabite woman married to a man from the tribe of Judah (Ruth 1:4). And according to the law of Moses "No Ammonite or Moabite shall be admitted to the assembly of the Lord. Even to the tenth generation, none of their descendants shall be admitted to the assembly of the Lord" (Deuteronomy 23:3). After she was widowed she was taken in marriage by Boaz as the nearest relative (Ruth 4:10; see Matthew 22:24).
1:6 Bathsheba was the wife of a Hittite general fighting at the front in King David's army. She was brought to the palace by David, and became pregnant. To cover himself he had her husband despicably put into the front of a siege attack to be killed (2 Samuel 11:1-17).
1:7-15 A comparison 1:6 with Luke 4:5 suggests that one group of genealogists rejected the line of Solomon, and preferred another line through Nathan. But the two lines met in Zerubbabel (1:12; Luke 3:27), and then after a long period of obscurity the royal line converged again in Joseph (1:16; Luke 3:23).
As in any monarchy there are cases where the proper genealogy can be questioned. This was especially the case in the ancient practices of adoption or a brother raising up a son for his brother's widow (Matthew 22:24). This may result in differences in the way some genealogies are listed.
1:16-17 Whatever the explanation of the different genealogical trees, Matthew makes it obvious that no one ever questioned Jesus' legal right to the throne of David. Everybody knew that an ancient monarchy descends by proper genealogy. If this legal right could have been questioned Jesus' messianic claim would have been undercut immediately. So if Jesus' title to the messianic line had been in doubt, it seems unlikely that the crowds would have welcomed him into Jerusalem (21:9). And a minimum of investigation would have convinced the high priests that Jesus could have no claim to be King of the Jews (26:65; 27:42). Even Pilate had no doubt about the legal title (27:11, 22, 37).
Matthew pointedly uses the term Messiah twice at the end of his genealogy (1:16, 17). For many people that term, and the genealogical tree that Matthew uses to introduce his Gospel, would seem irrelevant. But for the Jews of that day, who knew the Old Testament, the messianic significance of the evidence from genealogy that Matthew gives would certainly catch their attention.
The question of Jesus' paternity would naturally arise. And Matthew carefully explains that Joseph was the only known legal heir of the Davidic line, and he gave Jesus the legal right to the throne of David by accepting him as his son. Luke's Gospel explains that this was done when the baby Jesus, immediately after his birth, was registered in the Bethlehem census records (Luke 2:5-7).
It is interesting that the Gospels give no hint of anyone questioning Jesus' right to be the Messiah because of a faulty genealogy. This would have been the easiest way to silence the first Christians during Jesus' lifetime and during the years before Matthew wrote his Gospel. And if there had been some objection we can imagine the Gospels would have explained how the objection was answered.
1:18 In ancient cultures till comparatively recently the financial arrangements for a marriage were settled by the family in a betrothal, often long before the couple began living together. The actual marriage took place when the couple first shared the same bed. So Matthew explains that Mary and Joseph were legally betrothed, but she had become pregnant "before they lived together."
1:19-20 Joseph had decided to terminate the betrothal arrangement for obvious reasons, but his mind was changed by a dream (as in 2:13, 19, 22).
The Messiah had to come from the Davidic line and so Matthew emphasizes that Joseph is called "Joseph, son of David", and Jesus' conception was by the Holy Spirit (as in Luke 1:32, 35; 2:4).
1:21 The name Jesus is the same as the Old Testament Joshua, which is connected with a verb that means to help, save, rescue. Matthew did not choose to use the terms Saviour and salvation anywhere in his Gospel. Instead he focuses on showing how Jesus is the Messiah, and that term is sufficient to include all that Jesus does to save us.
As in many Old Testament references, salvation from sin is not limited to forgiveness but to all that God does to perfect us (Psalm 25:4-5; 51:10-12; see Matthew 5:2 ff.; 6:33; 9:35; 13:23; 18:2; 19:23-26). And as the Gospel proceeds Matthew will make clear that the main way the Messiah changes us is by teaching us his Word (11:1, 29; 13:52; 28:20).
1:22-23 This is the first of many quotations and allusions from the Old Testament, and in many cases we find it hard to make the logical connection which Matthew took for granted. In this case the text quoted refers to a miraculous sign. "The Lord himself will give you a sign" (Isaiah 7:14).
It is hard to see how a young woman giving birth to a male child would be significant. If she was a virgin, and known to be so, the birth would be both a sign to the unbelieving king in the days of Isaiah and an appropriate comparison for Matthew to use. Matthew makes similar Old Testament comparisons which we will note in 2:17-18; 3:3; 4:15-16; 11:10; 13:14-15, 35, 15:7-9; 21:13, 16, 42; 22:44; 24:29; 26:31; 26:64.
Emmanuel (from el which means "God," and immanu meaning "with us") is an appropriate name for the Messiah. He not only intervenes in a great deliverance, but is personally very present with us as in "The Word became flesh and lived among us" (John 1:14).
1:24-25 Joseph obeyed God's commandment given through the dream (for a major change in direction as in 2:13, 19, 22). In this case he did not terminate the betrothal, but took Mary to his home as his wife. In the delicate situation there was no marriage feast or religious ceremony. And whereas marriage was usually consummated by sexual intercourse, Matthew is careful to point out that in this special case this did not happen till after Jesus was born.