Gill, in his commentary, gives us a useful summary of this chapter.
‘This chapter relates the genealogy of the tribes that lived on the other side of Jordan, of the Reubenites, 1 Chronicles 5:1, of the Gadites, 1 Chronicles 5:11 of the half-tribe of Manasseh, 1 Chronicles 5:23 and of their war with the Hagarites, in conjunction with each other, and their conquest of them, 1 Chronicles 5:18 and who for their sins were all carried captive by the king of Assyria, 1 Chronicles 5:25.’
Although Reuben was the firstborn of Israel, he lost his inheritance because he slept with his father’s concubine, Bilhah, Genesis 35:22 / Genesis 49:3-4, and so, Joseph’s sons were given the firstborn rights. It was Judah who was given the blessing of being the one through whom the Messiah would come, Revelation 5:1-7.
Barnes, in his commentary, says the following.
‘His birthright was given. In particular, the right of the firstborn to a double inheritance, Deuteronomy 21:17, was conferred on Joseph, both by the expressed will of Jacob, Genesis 48:22, and in the actual partition of Canaan, Joshua 16-17. But though the birthright, as respecting its material privileges, passed to Joseph, its other rights, those of dignity and pre-eminence, fell to Judah; of whom came the chief ruler, an allusion especially to David, though it may reach further, and include a glance at the Messiah, the true ‘Ruler’ of Israel, Micah 5:2.’
Coffman, in his commentary, says the following.
‘Despite the fact of the double portion, normally the right of the first-born, having been transferred to Joseph, the Chronicler thought that the birthright of Joseph was nullified by the apostasy of North Israel and that the blessing of the leadership of God’s people was transferred to Judah.’
No one knows why the sons of Reuben are different from those found in other listings, Genesis 46:9 / Exodus 6:14 / Numbers 26:5. Tiglath-Pileser, the Assyrian king, is the same person as Pul, 2 Kings 15:29 / 2 Kings 16:7. Pul was his personal name which he retained as king of Babylon, and Tiglath-Pileser is his throne name as the king of Assyria.
The Hagrites were descendants of Hagar through Ishmael, Genesis 25:12-18 / 1 Chronicles 27:30-31 / Psalms 83:6. The descendants of Reuben uprooted these Hagrites, captured their property and their tents, and lived in their land.
The information given in Numbers 26:15-18 is omitted in this context.
Matthew Henry, in his commentary, says the following concerning the tribe of Gad.
‘Some great families of that tribe are here named, 1 Chronicles 5:12, seven that were the children of Abihail, whose pedigree is carried upwards from the son to the father, 1 Chronicles 5:14-15, like that, 1 Chronicles 5:4-5, is brought downwards from father to son. These genealogies were perfected in the days of Jotham king of Judah but were begun some years before, in the reign of Jeroboam II, king of Israel, 2 Kings 14:16 / 2 Kings 14:28 / 2 Kings 15:5 / 2 Kings 15:32. What particular reason there was for taking these accounts then does not appear, but it was just before they were carried away captive by the Assyrians, as appears, 2 Kings 15:29 / 2 Kings 15:31.’
The war mentioned here against the Hagrites is probably the same war which was mentioned back in 1 Chronicles 5:10. Because they put their trust in God, God answered their prayers and gave them the victory.
Clarke, in his commentary, says the following.
‘This was a war of extermination as to the political state of the people, which nothing could justify but a special direction of God; and this he could never give against any unless the cup of their iniquity had been full. The Hagrites were full of idolatry, 1 Chronicles 5:25.’
Coffman, in his commentary, says the following.
‘1 Chronicles 5:18-22 records an important victory over their enemies by the trans-Jordanic tribes, no record of which is found elsewhere in the Bible. This should warn us against assuming that the Bible records any such thing as a complete history of God’s people. There may be many other gaps in Samuel and Kings which Chronicles does not fill. Many of the events mentioned in this chapter are recorded in Genesis 25 / Genesis 35 / Genesis 49 / Exodus 6 / Joshua 22:11 / Numbers 1:20 / Numbers 26:5.’
One half of the tribe of Manasseh settled on the east side of the Jordan River and the other half settled on the west side of the river.
Coffman, in his commentary, says the following concerning the king of Assyria carried them away.
‘This was the captivity of the tribes of Israel which inhabited the country east of Jordan. It took place eleven years prior to the fall of Samaria (722 B.C.), that is, in 733 BC.’