In the Book of Numbers, certain tribes of Israel are clustered together. We see this in Numbers 2, which places three tribes on each of the four sides of the Tabernacle. The same clusters appear in Numbers 7, in which leaders of the tribes bring gifts to the Tabernacle. And, in Numbers 10:11-28, we see the order in which each tribal cluster moves out from Sinai.
Why are certain tribes grouped with certain other tribes? And why are these tribes put in a particular order—-i.e., Judah is first, etc.? In this post, I’ll address this question by appealing primarily to Genesis 29:31-30:24, in which Leah and Rachel give birth to the fathers of the tribes of Israel.
The first tribal cluster consists of Judah, Issachar, and Zebulun. They camp on the east side of the Tabernacle, and they are also the first three tribes to bring gifts to the Tabernacle in Numbers 7. Moreover, they are the first to depart from Sinai. Judah appears to precede Issachar in importance, and Issachar appears to precede Zebulun.
Judah, Issachar, and Zebulun are the third, fourth, and fifth sons, respectively, of Jacob’s wife Leah. So why are they the most important cluster, and not Leah’s first, second, and third sons? Leah’s first son, Reuben, was disqualified as firstborn because he slept with Jacob’s concubine (Genesis 35:22; 49:3-4; I Chronicles 5:1). Leah’s second and third sons were Simeon and Levi, respectively, and they were scattered in Israel because of their slaughter of the Shechemites (Genesis 34:25-31; 49:5-7). Consequently, Judah, Issachar, and Zebulun, the next in line, appear to take their place as the most important tribes.
The second tribal cluster consists of Reuben, Simeon, and Gad. As I said above, Reuben and Simeon are the first and second sons, respectively, of Leah. Leah’s third son, Levi, is not included in this cluster because the Levites were to be servants of the Tabernacle, and so they were not a part of any tribal cluster. The third tribe, Gad, is the firstborn son of Leah’s maid Zilpah.
The third tribal cluster consists of Ephraim, Manasseh, and Benjamin. Ephraim and Manasseh are sons of Joseph, the son of Rachel. Ephraim precedes Manasseh in importance in Numbers just as he does in Genesis 48, in which Jacob blesses his grandsons and makes them like his own sons. And Benjamin is the second son of Rachel. The sons of Leah come first in importance, and then the sons of Rachel follow. Could this be because God honored Leah as the underdog, the wife whom Jacob did not love (see Genesis 29:31)?
The fourth tribal cluster consists of Dan, Asher, and Naphtali. Dan is the firstborn son of Rachel’s maid Bilhah, and, as Jacob Milgrom notes, he is the first among the sons of Israel to be born to one of Jacob’s concubines, which, according to Milgrom, is probably the reason that Dan is the head of this cluster. Naphtali is the second son of Bilhah and the second son born to one of Jacob’s concubines. And Asher is the second son of Leah’s maid Zilpah. Remember that the first son of Leah’s maid Zilpah, Gad, is in the second tribal cluster, along with Leah’s first and second sons.
The general pattern here is that Leah’s sons come first, then Rachel’s sons follow, and finally we have the sons of the concubines. But this pattern is not air-tight, for there needed to be a third person in the second cluster for there to be twelve tribes surrounding the Tabernacle, and this was solved by putting the first son of Leah’s maid into it. Moreover, while the order of birth often determines the importance of the tribes in terms of their arrangement, that is not an absolute, for the first cluster is younger than the second cluster, and Ephraim is younger than Manasseh yet is more important.