A second point of tension is found in the differences between Matthew and Luke’s genealogies of Jesus. Matthew’s genealogy runs from Abraham down to Jesus in three groups of 14 generations. Luke’s genealogy goes from Jesus all the way back up to Adam, and indeed God before him.
While the two genealogies are similar between Abraham and David, they diverge dramatically between David and the exile, meeting for Shealtiel and Zerubabel, before diverging again and only meeting with Jesus’s legal father, Joseph. Consequently, Joseph is presented as having two different fathers: Jacob in Matthew and Eli in Luke. Often people seek to harmonise these two genealogies by saying that one of them is actually the genealogy of Mary, though there’s nothing in the text to support that.
The different genealogies are confusing to modern readers, most of whom have some sense of what they expect a genealogy to be. Our culture loves the idea of tracing our family line. We have television programmes devoted to ancestral research, websites for filling out your family tree, and in just a few clicks you can have a genetic testing kit delivered to your door. To us, genealogies record faithfully and accurately our lineage, step-by-step, through the generations, without missing any out.
But what if that’s not what a genealogy was in the ancient world? What if genealogies were used in a different way, to present different information? To assess the historicity of the gospel genealogies, we need to recognise that our modern-day notions may not transfer to the ancient world.
The two gospel genealogies make different points. Matthew traces from Abraham through the royal line to Jesus, and strikingly mentions four women who were either non-Israelite (Tamar, Rahab, Ruth) or at least had foreign connections (Uriah’s wife). Among other things this prepares us for the end of the book, which shows the gospel going to all nations.
Luke’s genealogy connects Jesus with the first man and helps us to think of the contrasts between Jesus and Adam (and all other humans generally). It’s a perfect prelude to the temptation narrative in Luke 4:1–13 in which Jesus refuses food in the barren desert in contrast to Adam who took the forbidden fruit in a garden full of other fruit.
In terms of the different accounts of Joseph’s father, it’s not difficult either today or back then to imagine that someone might have a legal father other than his biological one, especially if Joseph’s biological father disowned him over the shame of Mary’s irregular pregnancy. But there are a few other interesting things to notice about the genealogies. First, though they give different grandfathers for Jesus, the name of his great-grandfather in both genealogies is almost identical: Matthan in Matthew and Matthat in Luke. The only difference is in the final consonant, and this is of a kind that is readily explicable: these names reflect two Hebrew words — mattan and mattat — both of which mean “gift”.
Secondly, taking our cue from this name, we see that a number of the names in Luke’s genealogy share a single root. The name Matthat along with five other names in the genealogy after David come from the Hebrew three-consonant root NTN which means “give”. (Sometimes the Ns are hidden by turning into Ts.) These are Mattathias (3:25), Mattathias (3:26), Matthat (3:29), Mattatha (3:31), and Nathan (3:31). This makes some sense as this is the genealogy through David’s son Nathan. The root for “give” was used to form some of the most popular names of Nathan’s descendants. As is common in families, names are repeated. There are three Josephs, two Levis, two Melchis, and the name Er (3:28), which is only ever attested for the tribe of Judah (see Genesis 38:3). These are features we might expect in a true narrative. We may also note that the genealogy doesn’t blunder by having any of the popular Greek names, such as Philip or Herod, for the period before Alexander the Great.
Thirdly, in both Matthew and Mark we’re told the names of Jesus’s brothers: James, Joseph, Simon, and Judas (Matthew 13:55) or James, Joses, Judas, and Simon (Mark 6:3). These differ only in the order of the final two names and in the adaptation of the Hebrew name Joseph to a Greek ending in the form Joses in Mark. However, these names also link with the genealogy in Matthew. Boys were often called after their grandfathers (a practice known as papponymy) and sometimes after their father (patronymy). If Jesus’s name was indeed given by the angel as stated in Matthew 1:21, then neither the father’s nor the grandfather’s name was an option. However, we see both these names used in the family. James is usually understood to be the first son born to Joseph and Mary after Jesus’s birth. He was therefore called James, or strictly Jakobos, ie his grandfather’s name Jacob with the Greek noun ending -os. Jakobos evolved into English as James through centuries of sound changes. The next son after Jakobos was named after his father Joseph.
Thus we can see in the names of Jesus’s brothers a tiny coincidence which supports Matthew’s genealogy.