Every student of the Bible at one point or another comes to certain portions of Scripture that create confusion, perhaps mixed with a tinge of boredom or imagined insignificance. One such portion is the genealogies found across the Old Testament. This post will examine in cursory fashion a smattering of these genealogies, giving attention to some general considerations of their form, how they function in a text, and conclude with a brief word on the purpose they serve. In so doing, the reader will grasp the importance genealogies play in societies in general and that of the nation of Israel in particular. It is easy to assign one all-encompassing reason for the presence of genealogies in OT, but that would be reductionistic and ultimately unhelpful; genealogies are much more expansive and layered than most readers often assume.
I. The Nature of Genealogies
In a sentence, genealogies are a record of a person’s ancestral descent. Although genealogies can be passed down in oral fashion, we have them in their canonical-literary form in various portions spread throughout the Old Testament, some short and some long.
One helpful distinction made by scholars is that of linear and segmented genealogies. The former provides the name of an individual and then connects him/her to a generation prior (e.g., son and father, etc.), while the latter can do the same while also providing information within a generation (e.g., brother to brother, etc.). For example, in Genesis 5:3-31 there is a linear genealogy, listing the line from Adam to Noah, one generation at a time. The format is simple enough: When A had lived X years, he fathered B. Also in the book of Genesis, in Gen. 10:1-32, one finds a segmented genealogy. In this example, the emphasis is not so much on the continuity of one generation to the next but rather the geographical spread of Noah’s three sons.
I will examine these two examples in greater detail below, but at this point it is good to note that this distinction should not be pushed too far since at times both linear and segmented genealogies appear together. In such cases, the transition marks the significance or insignificance of a specific generation. A good general rule, as J. W. Wright explains in his discussion on the Pentateuch, is that “linear genealogies . . . tend to connect characters at the center of the unfolding of the plot; segmented genealogies tend to fill out the families of characters who no longer will play a central role in the . . . story.”
A few other odds and ends include the distinction between patrilinear versus matrilinear genealogies; most genealogies in the OT trace the line through the father. Additionally, genealogies can vary in length, although obviously they must consist of at least two generations. There are twenty-six generations from Solomon to the sons of Elioenai in 1 Chronicles 3:10-24. And lastly, there is a degree of fluidity among genealogies where details can vary in various circumstances: (1) a change in relationship among individuals, (2) or an addition of persons or families to the society; (3) or when telescoping is used (i.e., names are removed).
II. The Function of Genealogies
It would be easy to assign one overall function to genealogies, but in so doing one would miss the richness of their use in the Old Testament. In this section I will list several functional categories and will seek to provide examples of each.
(1) Social Function
There is a social function to genealogies, especially of the segmented sort, which explore the kinship relationships between individuals. At a horizontal level, these genealogies show the equality of individuals in relation to one another; at the vertical level, they show a level of hierarchy and hence of inequality, not in the inferior sense but that of different role and purpose (e.g., those descended of Levi were priests and thus a man from the tribe of Gad could not become a priest). Another important feature of segmented genealogies is that the OT does not only contain the descendants of the children of Israel but also preserves that of surrounding nations (e.g., Gen. 10:6-7, 21-31; 22:20-24; 25:1-6, 12-20; 36), which serves to show Israel how to relate to its neighbors among other reasons.
(2) Legitimizing Function
Another function of genealogies is the establishment of legitimacy. In other words, it confirms the legitimacy a certain person to be included in a group or to serve an official capacity or receive inheritance of a land. These appear most often in linear genealogies which “ground a claim to power, status, rank, office, or inheritance in an earlier ancestor.” For example, in Zephaniah 1:1 the prophet provides a linear genealogy: “Zephaniah son of Cushi, the son of Gedaliah, the son of Amariah, the son of Hezekiah, during the reign of Josiah son of Amon king of Judah.” Among the prophetic authors, only Zephaniah traces his lineage back to the fourth generation, highlighting its particular importance. The reference to Hezekiah, as Adele Berlin notes, suggests a connection to the kinds reforms, which “hints that Zephaniah’s apparent support of religious reform in his own day has an origin in his family history.” In this case, there is a certain weight of legitimacy given to Zephaniah’s ministry as he seeks to turn Judah back to the Lord.
On a similar front, this legitimizing role is at play in postexilic texts like Ezra and Nehemiah where Jews are returning home and the priesthood needs to be reestablished. It is clear that descent from Aaron was a necessary qualification for the priesthood (cf. Num. 16:40). Unless such lineage could be proven, there would be no right to claim priestly prerogatives or roles. Ezra 2:62 unequivocally states that certain individuals’ names were not found in the family records and as a result were “excluded from the priesthood as unclean.” The emphasis here is on a rigid safeguard to ensure the purity of devotion to the Lord.
(3) Theological Function
The most notable and lengthy of the OT genealogies is found 1 Chronicles 1-9. Most readers often skim over this section if not outright ignore it. H. G. M. Williamson is correct in observing that “few biblical passages are more daunting to the modern reader than the opening chapters of 1 Chronicles.” Even modern commentators face this daunting challenge. Adam Welch, for example, believes these genealogies were not original to the book of Chronicles because they “have no unity among themselves and are not integrally related to the rest of the book.” But this assertion need not be so. The problem often arises when modern readers impose modernistic assumptions on the text, demanding a purely historical purpose to the genealogies inclusion in Chronicles.
For sake of space, I argue that the Chronicler’s use of genealogy gives a panoramic view of the human background of emergence of the nation of Israel. Two key theological features in this use of genealogy, when taken as a whole, is (1) the hope-giving confidence that God is sovereign over the course of history and that (2) God is faithful to his covenant people. Moreover, this genealogy culminates in the Chronicler’s present day with his own generation, tucked away in exile in the Persian Empire. The entire sweep of history beginning with Adam in 1 Chronicles 1:1 is closely tied with the legitimizing function but it is more in that it gives this small remnant a sense of history rooted in the character and promises of God.
Another theological function is found in Genesis 5:3 where it says, “When Adam had lived 130 years, he fathered a son in his own likeness, after his image, and named him Seth” (emphasis mine). This is clearly a hearkening back to Genesis 1:26 where God says, “Let us make man in our image, after our likeness.” The inversion of the order is a literary device that points back to the original statement. Moreover, as Wilson notes, “Adam genealogically transmits the divine image and the blessing to his son. The entire linear genealogy thus deals with the transmission of the divine image and the blessing through a series of firstborn sons. The genealogy thus has a theological function.” The author of Genesis thus makes a theological point that the image and likeness of God continues down the line of Adam. More to the point, the Fall of man in Genesis 3 does not entirely obliterate the image and likeness of God in which he was created.
(4) Historical Function
The historical function serves to order the information of the past in order to make sense of and better understand the present. The clearest example of this is the concluding verses in the book of Ruth. There are ten generations listed, from Perez to David. If the purpose of genealogy was purely to demonstrate the royal line of David, then reference could have been made to Judah, the father of Perez, who after all received Jacob’s prophetic blessing that the “scepter” would depart from Judah (Gen. 49:10). Instead, it seems more likely that this genealogy was appended in order to fill out some of the historical details; reference was made to Perez and David in verses 12 and 17 respectively, and so the reader would naturally ask, How did we get here? Daniel Block, therefore, maintains that the key to this genealogy’s inclusion is found in the narrative section that precedes it and the relative silence as to the connection of these characters.
(5) Literary Function
We have already examined the theological function of 1 Chronicles 1-9 above; but it also contains a literary function. Of special importance is the Chronicler’s portrayal of the tribe of Levi. In terms of both location and amount of space devoted to it, Levi’s tribe serves a central role in this genealogy. Gary Knoppers identifies a broad chiastic structure of this section:
a. The peoples of the world (1 Chr. 1:1-54)
b. Judah (1 Chr. 2:3-4:23)
c. Simeon and the Transjordanian tribes (1 Chr. 4:24-5:26)
d. The tribe of Levi (1 Chr. 5:27-6:66)
c’. The northern tribes (1 Chr. 7:1-40)
b’. Benjamin (1 Chr. 8:1-40)
a’. The Persian period inhabitants of Jerusalem (1 Chr. 9:2-34)
Observing a similar arrangement, Brian Kelly argues that “Levi is placed in the literary and spiritual center of the Chronicler’s ideal conception of Israel.” Along with Judah and Benjamin, the Chronicler also suggests that Levi will play an essential role in maintaining Israel’s heritage in post-exile as it had done so in the past. Again, there is a legitimizing element at play here since there is a need for purity of descent within the priesthood, especially in the postexilic period.
Another literary dimension is the genealogical inclusion in narrative sections. One easy example of this is Ruth 4:18-22, which we already examined in detail above: the presentation of a ten-generation-long genealogy, however simple, speaks volumes to the reader as to the promise-keeping nature of God (cf. 2 Sam. 7:16).
(6) Military Function
The census list in Numbers 1:3-46 (and then re-done thirty-eight years later in 26:4b-51), although not a classic genealogy, functions in many ways like a genealogy. The most immediate reason for its inclusion in the book of Numbers is to count all the men over the age of twenty (Num. 1:3) who would be fit for military service — a kind of preliminary draft. The repetitive formula in this census is (1) tribal nomenclature, (2) military conditions of enlistment, (3) clan and familial basis, (4) tribal name reiterated, (5) tribal total.
To better understand the nuanced and multi-layered function of genealogies, consider that the Levites are exempted from military services and were instead to carry and care for the tabernacle (Num. 1:50). In this small example, then, we find an element of the social function; there is an explanation and reiteration of social responsibilities among the various tribes. Moreover, there is a ethical affirmation of Israel’s faithful obedience — however short-lived — to the Lord in taking the census (Num. 1:54) and a theological affirmation of God’s covenant-keeping promises. Dennis Olson succinctly sums these various elements together:
Although the lists in Numbers display a somewhat altered form from the genealogies and tribal lists of the book of Genesis, they perform similar literary and theological functions. They mark major structural divisions. They make a theological claim about the continuity of the covenantal promises and laws given to the patriarchs for each succeeding generation. They make a theological claim for the inclusiveness of the covenant promises and laws for all Israel. Furthermore, the expanded segmented genealogies of Numbers 26 suggests a partial fulfillment of the promise of an abundance of descendants which was given to the patriarchs in the Genesis narrative.
It is clear, then, that while a genealogy may function militarily, it also serves in a theological sense and social sense among others.
III. Brief Word on Purpose
For the sake of clarity of argument, this post has sought to somewhat neatly categorize the various functions of genealogies, and obviously many clearly operate on one or two main levels. But the nature of the Old Testament and the God that it gives testimony to, does not allow the modern reader to impose these categories onto the text as a straightjacket. Instead, these categories serve as an invitation to us modern readers to better grasp initially off-putting passages like genealogies.
This study serves to remind us, as Paul told Timothy in reference to the Old Testament, “[a]ll Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness” (2 Tim. 2:16). The purpose of Old Testament genealogies is the purpose of Scripture: to transform God’s people in all ages into a righteous people ready to serve him in every good work. Although seemingly jarring or boring at first, genealogies (1) remind us God’s care and concern for individuals; (2) they remind us that God cares for how his people relate to each other and others around them; (3) they remind us that God’s infinitely concerned with his own holy standards while at the same time patient with weak and sinful people; (4) they remind us that God always has had and will always have a faithful remnant through the ages; (5) they remind us that God keeps his covenant promises; (6) they remind us that God is intimately acquainted with and sovereign over every epoch of human history; (7) they remind us that God uses an unworthy people to act both as his emissaries of grace and swords of judgment; (8) and they remind us that God is wonderfully creative, and among the various genres of Scripture one of them is genealogy.
 Of course, there are genealogies in the NT (Matthew 1:1-17; Luke 3:23-38). The focus of this purpose, however, is solely on those in the OT.
 So D. S. Huffman, “Genealogy,” in Dictionary of Jesus and the Gospels, ed. Joel B. Green and Scot McKnight (Grand Rapids: InterVarsity Press, 1992), 253.
 J. W. Wright, “Genealogies,” in Dictionary of the Old Testament: Historical Books, ed. T. Desmond Alexander and David W. Baker (Grand Rapids: Inter-Varsity Press, 2003), 346.
 So ibid.
 James T. Sparks, The Chronicler’s Genealogies: Toward an Understanding of 1 Chronicles 1-9, Academia Biblica 28 (Atlanta: Society of Biblical Literature, 2008), 15. The LXX allows four more generations, giving thirty in total. Cf. Gary N. Knoppers, I Chronicles 1-9: A New Translation with Introduction and Commentary, The Anchor Bible (New York: Doubleday, 2003), 334.
 Robert R. Wilson, Genealogy and History in the Biblical World (New Haven: Yale University Press, 1977), 27–36. See also Sparks, The Chronicler’s Genealogies: Toward an Understanding of 1 Chronicles 1-9, 18–21.
 These categories are adapted from Marshall D. Johnson, The Purpose of the Biblical Genealogies, 2nd ed. (Eugene, OR: Wipf & Stock Publishers, 2002); John H. Walton, “Genealogies,” in Dictionary of the Old Testament: Historical Books, ed. Bill T. Arnold and H. G. M. Williamson (Downers Grove, IL.: IVP, 2005), 309–316.
 Robert R. Wilson, “Genealogy, Genealogies,” in The Anchor Bible Dictionary, vol. 2 (New York: Doubleday, 1992), 931.
 Kenneth L. Barker, Micah, Nahum, Habakkuk, Zephaniah, New American Commentary 20 (Nashville: Broadman & Holman, 1998), 408–409.
 Adele Berlin, Zephaniah: A New Translation with Introduction and Commentary, The Anchor Bible 25A (New York: Doubleday, 1994), 65.
 H. G. M. Williamson, 1 and 2 Chronicles (Grand Rapids: Eerdmans, 1982), 38.
 J. A. Thompson, 1, 2 Chronicles, New American Commentary 9 (Nashville: Broadman & Holman, 1994), 48.
 Cf. ibid., 48–49. For a helpful extended discussion on this theme, see Michael Wilcock, The Message of Chronicles: One Church, One Faith, One Lord, The Bible Speaks Today (Downers Grove, IL: Inter-Varsity Press, 1987), 19–31.
 So K. A. Mathews, Genesis 1-11:26, New American Commentary 1A (Nashville: Broadman & Holman Publishers, 1996), 310.
 Wilson, Genealogy and History in the Biblical World, 164.
 So Walton, “Genealogies,” 313.
 So Daniel I. Block, Judges, Ruth, New American Commentary 6 (Nashville, Tenn: Broadman & Holman Publishers, 1999), 735.
 Ibid., 736.
 Reproduced from Knoppers, I Chronicles 1-9: A New Translation with Introduction and Commentary, 261.
 Brian E. Kelly, “1 and 2 Chronicles,” in The ESV Study Bible, ed. Wayne Grudem, C. John Collins, and Thomas R. Schreiner (Wheaton: Crossway Bibles, 2008), 711.
 Knoppers, I Chronicles 1-9: A New Translation with Introduction and Commentary, 264.
 R. Dennis Cole, Numbers, New American Commentary 3B (Nashville: Broadman & Holman, 2000), 76–77.
 Dennis T. Olson, The Death of the Old and the Birth of the New: The Framework of the Book of Numbers and the Pentateuch, Brown Judaic Studies 71 (Chico, CA: Scholars Press, 1985), 187, quoted by Cole, Numbers, 76.