I realize I run the risk of ruining my reputation, if ever I say anything positive about the three-year lectionary. All the more so if I offer any hint of constructive criticism concerning the historic (medieval western) lectionary. I have no beef with the historic lectionary, but neither do I regard it as the litmus test of orthodoxy that many of my dear friends and colleagues hold it to be. It has its strengths and, dare I say, its weaknesses; so does the three-year lectionary. Normally, though, because I have grown weary of arguing about it, I simply bite my tongue and swallow any comments I might otherwise offer.
I'm throwing caution to the wind in this case, however, because I have been struck by a realization this past week that still leaves me curious. Advent Tide in the three-year lectionary features prominently the preaching of repentance by St. John the Baptist, especially from St. Matthew (in Series A) and St. Luke (in Series C), and to the extent that St. Mark records it (in Series B). I think this is a good thing, which accords well with the good purpose for which the holy Evangelists recorded St. John's preaching. What has struck me, in particular, is that this preaching does not occur in the historic lectionary, leastwise not on any of the Sundays (neither in Advent Tide, nor elsewhere in the course of the year). It does seem likely that it may be among the Lections appointed for weekday Masses in the historic Roman missal, but I'm not sure to what extent those have found a regular place among Lutherans. Granted, the historic Fourth Sunday in Advent features the important words of St. John the Baptist as recorded by St. John the Evangelist, but that is a decidedly different sort of proclamation than his preaching of repentance in the three Synoptic Gospels.
Not only that, but the historic lectionary has tended to relegate the Baptism of Our Lord to relative obscurity, although that occasion has floated about a bit between Christmas Tide and the first week of Epiphany Tide. The Lutheran Service Book redaction of the historic lectionary has taken the liberty of listing the Baptism of Our Lord as the first option for the First Sunday after the Epiphany, following the lead of the three-year lectionary in that instance. Heretofore, I have to wonder to what extent the Forerunner's preaching and Baptism of repentance were heard among those following the historic (medieval western) lectionary. I also wonder why it may have been so limited, because that does not seem like such a good thing to me.
I realize that, of course, the work of St. John the Baptist was historically fulfilled and completed with the first Advent of the Christ in the flesh. Clearly, John does decrease and Christ increases, and that is only right. But I maintain that the office of the Forerunner necessarily continues, as the Advent of Christ also continues in the Ministry of the Gospel. In any case, the Evangelists not only record the preaching of St. John (as more than a bit of historic trivia, I warrant), but they also summarize the preaching of Christ and His Apostles as a continuation of St. John's preaching: "Repent! for the Kingdom of Heaven is at hand." The preaching of St. Peter on Pentecost Day is once more an echo of the Forerunner's preaching: "Repent, and be baptized!" And when our Lord Himself was questioned as to His authority, He linked Himself specifically to the authority with which St. John the Baptist had been sent. In light of all of this, it seems to me that the actual preaching of St. John, as recorded especially by St. Matthew and St. Luke, is a proclamation that needs to continue in the life of the Church on earth, as the very means by which the Lord prepares His way before Him.
For my part, I am very pleased and satisfied with the way in which the LSB three-year lectionary handles the end of the Church Year and the Season of Advent, which historically belong together as a penitential period of waiting upon the coming of Christ. Each of the three years offers its own nuances, but they all retain essentially the same basic pattern and movement. The eschatological preaching and emphasis of Advent 2 in the historic lectionary, sound forth in the final Sundays of the Church Year, and then the ministry of St. John the Baptist comes into focus on the Second and Third Sundays in Advent. In this way, the LCMS Proper Preface for Advent seems less like reminiscing and more the confession of what the Lord is still doing among us. The entry of our Lord into Jerusalem is given preference on the First Sunday in Advent, reclaiming that salutary keynote to the Church Year, and the coming of our Lord in the womb of the Blessed Virgin Mary characterizes the Fourth Sunday in Advent. Waiting with a woman for the birth of her child seems most appropriate, not only in anticipation of Christmas, but also as the Church experiences the "birth pangs" of the approaching judgment.