On the Sunday occuring on December 11 through 17, the Byzantine Church celebrates the "Sunday of the Holy Ancestors of Christ." We have nothing quite comparable in the Western calendar. The closest approximation might be the feast (reduced since 1969 to memoral) of Saints Joachim and Anne, parents of the Blessed Virgin Mary. But that comes in July and is celebrated in a quite different liturgical context. December 17, however, traditonally marks a certain turning point in the Advent season, the liturgy of the weekdays from today through December 24 all being "ordered in a more direct way to preparing for the Nativity of the Lord" (Universal Norms on the Liturgical Year and the Calendar, 42). Fittingly, therefore, the Gospel today is taken from the beginning of the Gospel according to Matthew, the "genealogy" of Jesus (Matthew 1:1-17), which lists three sets of 14 generations highlighting Jesus' descent from Abraham and David.
"To the modern reader," Raymond Brown famously wrote (The Birth of the Messiah, 1979), "there are few things in the Bible less meaningful than the frequent lists of descendants or ancestors." Obviously Brown did not share that view. (In fact, I think it was Brown - if not, it was someone comparably prominent - who once lamented that the genealogy got left out of the Sunday lectionary). In any event, neither does the Pope, who devotes much of the first chapter of his latest book (Jesus of Nazareth: The Infancy Narratives) to Matthew's and Luke's genealogies. The sub-title of that first chapter sort of says it all: "The Question about Jesus' Origin as a Question about Being and Mission."
Thus, regarding Matthew's genealogy, the Pope observes that "the focus is already on the end of the Gospel, when the risen Lord says to the disciples: 'Make disciples of all nations' (Mt 28:19). In the particular history revealed by the genealogy, this movement toward the whole is present from the beginning: the universality of Jesus' mission is already contained within his origin."
The presence of four Old Testament women in the genealogy - Tamar, Rahab, Ruth, and Bathsheba (the wife of Uriah the Hittite) - has (at least since Martin Luther) been seen as consonant with this theme of universality, since they were all four presumptively foreign, gentile women. "So through them," the Pope writes, "the world of the Gentiles enters the genealogy of Jesus - his mission to Jews and Gentiles is made manifest."
Earlier, St. Jerome had argued that the four Old Testament women were sinners, and so their includsion foreshadowed Jesus's role as savior of sinners. Brown doubts that Matthew's audience would have caught this, if in fact such was Matthew's intent. While the Pope acknowledges the view that the inclusion of those four Old Testament women "would serve to indicate that Jesus took upon himself their sins - and with them the sins of the world - and that his mission was the justification of sinners," he also acknowledges the limit to that interpretation in that it is not completely clear that all four were really seen as sinners.
The nice thing about scriptuire is that it is capable of bearing multiple meanings. Neither of the above interpretations excludes the other, and neither excludes what has become the most popular interpretation today - that each of the four involved exceptional circumstances making posible the continuation of the messianioc line, leading logically to the most exceptional circumstance of all, the virginal conception of Jesus by the fifth woman in the list, Mary. As the Pope puts it: "the final sentence turns the whole genealogy around. Mary is a new beginning."
Indeed, although a genealogy is by definition about the past, the genealogy of Jesus really is more about the new beginning the incarnation represents for the world. Without the past, there would, of course, be no present; but, in the story of salvation, past and present are both subordinate to the new future which the Gospel heralds.
Hence the importance of the genealogy and its appropriateness for today - just one week to go till Christmas. The genealogy, as the Pope notes, illuminates "the intricacy with which he [Jesus] is woven into the historical strands of the promise, as well as the new beginning, which paradoxically characterizes his origin side by side with the continuity of God's action in history."