How to sort out the many disparities between the genealogies of Matthew and Luke.
Problems in Scripture work like speed bumps: They may be frustrating, and they can do damage to the unwary, but they effectively slow us down and focus our attention. Tensions provoke thought. Apparent contradictions force us to wrestle with texts in greater detail. When God inspired them, he knew what he was doing.
Studying the Gospels, we immediately encounter the problem of major differences between the genealogies of Jesus in Matthew and Luke. Matthew 1 lists 42 generations going back to Abraham; Luke 3 has 77 generations going back to Adam. Of the dozens of names between David and Jesus, only five appear on both lists. Worse, Jesus has two different paternal grandfathers: Jacob (Matt. 1:16) and Heli (Luke 3:23).
Efforts to sort out the disparities often focus on Matthew’s side, partly because his genealogy looks more theologically motivated—the numerous gaps, the women who feature, the three groups of 14, and so on. Luke, we assume, is giving “just the facts,” while Matthew is fiddling with them to make a point. But this demeans both the historian in Matthew and the theologian in Luke. I think Luke’s genealogy has a theological agenda just as strong as Matthew’s, if not more so.
Consider how he lists 77 generations from Adam to Christ. That number points to the Sabbath. It reminds us of the 77-fold vengeance of Lamech (Gen. 4:24) and the 77-fold forgiveness of Jesus (Matt. 18:22). It evokes the Jubilee year (Lev. 25:8–55), observed once for every seven sets of seven years. Jesus proclaims his fulfillment of the Jubliee promise in Luke 4:16–21, a development foreshadowed two chapters earlier, when the summons to report home for a census recalls the Jubilee command to return …