How to Use Biblical Genealogies
Biblical genealogies serve a lot of helpful purposes. First, they show everyone's connection to everyone else. Understanding who's who, and how they're related to those around them is vital just to get what's going on. Second, they often have important Christological purposes. For example, Matthew and Luke follow different parts of Jesus' family tree, for pretty clear reasons. As the New American Bible explains in a footnote on Luke 3:31,
The son of Nathan, the son of David: in keeping with Jesus' prophetic role in Luke and Acts (e.g., Luke 7:16, 39; 9:8; 13:33; 24:19; Acts 3:22-23; 7:37) Luke traces Jesus' Davidic ancestry through the prophet Nathan (see 2 Sam 7:2) rather than through King Solomon, as Matthew 1:6-7.So if you want to emphasize that Jesus is King, show His lineage through David and Solomon. If you want to emphasize that Jesus is Prophetic, show His lineage through David's other son, Nathan the Prophet. Finally, these lineages also put a spotlight on otherwise forgotten people. There's something wonderful about the idea that a bunch of individuals otherwise lost to history are remembered by name in Scripture, for nothing more than raising a family. What an incredible message that sends to those moms and dads who live and die in seeming obscurity. Even if lost to the world, God knows you by name. And through Scripture, He brings honor to these people well after their death. Through the thankless act of raising godly children, they made straight the way for Christ's Incarnation, without even knowing it. It's almost like the "credits" reel at the end of the movie, a nod towards all of the obscure people whose work lead to something much bigger than themselves. So Biblical genealogies are important, and should be treated as God-breathed Scripture, even if (like credit reels) they're sort of boring to read.
How NOT to Use Biblical Genealogies
That said, there's one thing Biblical genealogies shouldn't be used for, and that's trying to construct a precise history. This has lead to all sorts of embarrassments for Christians who misuse these passages. Anglican Bishop James Ussher famously used Biblical geneologies (and some other sources) to argue that the Earth was created on October 23, 4004 B.C. He literally had calculated it down to the day. And then there's Harold Camping and his followers, who claim that Judgment Day will be May 31, 2011, and that the Earth will end on October 21st. I'd earlier thought they believed in May 31st for the world ending, but it turns out that they believe in something far more twisted:
They're wearing sweatshirts and other clothing announcing the "Awesome News," that Judgment Day is coming on May 21. On that day, people who will be saved will be raptured up to heaven. The rest will endure exactly 153 days of death and horror before the world ends on October 21For both Ussher and Camping, this math is based pretty extensively upon Scripture's genealogies. But here's the thing: those genealogies don't include everyone. This can be clearly deduced from Scripture itself. So here's the geneology found in Ezra 7:1-6, for example:
1 After these things, during the reign of Artaxerxes king of Persia, Ezra son of Seraiah, the son of Azariah, the son of Hilkiah, 2 the son of Shallum, the son of Zadok, the son of Ahitub, 3 the son of Amariah, the son of Azariah, the son of Meraioth, 4 the son of Zerahiah, the son of Uzzi, the son of Bukki, 5 the son of Abishua, the son of Phinehas, the son of Eleazar, the son of Aaron the chief priest— 6 this Ezra came up from Babylon. He was a teacher well versed in the Law of Moses, which the LORD, the God of Israel, had given. The king had granted him everything he asked, for the hand of the LORD his God was on him.It sounds like Ezra is saying that exactly fifteen generations before Seraiah was his ancestor Aaron, the chief priest. After all, each generation is connected by saying that A is "the son of " B. But 1 Chronicles 6:3-14 gives this fuller genealogy:
So it's not fifteen generations from Aaron to Seraiah. It's at least twenty-two, and that's assuming that 1 Chronicles isn't skipping anybody. This isn't unusual, as I've mentioned before. Scripture often says "father" and "son" where English-speakers would say "ancestor" or "forefather" and "descendant." To make it more complicated, there's a tradition of what's called papponymics, in which sons were often named after their grandfathers. You can see this in 1 Chronicles 6:7-11 above. The first Azariah is the father of Johanan, who then names his son after his dad. Azariah, Jr. then names his son Amariah, another family name. So that's why you see two men apiece named Ahitub, Amariah, and Zadok, and another three men each named Azariah.3 The children of Amram: Aaron, Moses and Miriam.The sons of Aaron: Nadab, Abihu, Eleazar and Ithamar.4 Eleazar was the father of Phinehas,Phinehas the father of Abishua,5 Abishua the father of Bukki,Bukki the father of Uzzi,6 Uzzi the father of Zerahiah,Zerahiah the father of Meraioth,7 Meraioth the father of Amariah,Amariah the father of Ahitub,8 Ahitub the father of Zadok,Zadok the father of Ahimaaz,9 Ahimaaz the father of Azariah,Azariah the father of Johanan,10 Johanan the father of Azariah (it was he who served as priest in the temple Solomon built in Jerusalem),11 Azariah the father of Amariah,Amariah the father of Ahitub,12 Ahitub the father of Zadok,Zadok the father of Shallum,13 Shallum the father of Hilkiah,Hilkiah the father of Azariah,14 Azariah the father of Seraiah,and Seraiah the father of Jozadak.
So for both of these reasons, trying to measure exact dates based upon genealogies which (a) often have multiple men with the same names, and (b) often have huge unsignaled gaps where a "father" is really the great-grandfather of the next man listed, is something of a fool's errand. So savor the genealogies for what they're for, but don't try and use them for what they're not for.