We have here an extract out of the genealogies,

I.Of the tribe of Reuben, where we have,

1.The reason why this tribe is thus postponed. It is confessed that Reuben was the first-born of Israel, and, upon that account, might challenge the precedency; but he forfeited his birthright by defiling his father's concubine, and was, for that, sentenced not to excel, Gen 49:4. Sin lessens men, thrusts them down from their excellency. Seventh-commandment sins especially leave an indelible stain upon men's names and families, a reproach which time will not wipe away. Reuben's seed, to the last, bear the disgrace of Reuben's sin. Yet, though that tribe was degraded, it was not discarded or disinherited. The sullying of the honour of an Israelite is not the losing of his happiness. Reuben loses his birthright, yet it does not devolve upon Simeon the next in order; for it was typical, and therefore must attend, not the course of nature, but the choice of grace. The advantages of the birthright were dominion and a double portion. Reuben having forfeited these, it was thought too much that both should be transferred to any one, and therefore they were divided. (1.) Joseph had the double portion; for two tribes descended from him, Ephraim and Manasseh, each of whom had a child's part (for so Jacob by faith blessed them, Heb 11:21; Gen 48:15, Gen 48:22), and each of those tribes was as considerable, and made as good a figure, as any one of the twelve, except Judah. But, (2.) Judah had the dominion; on him the dying patriarch entailed the sceptre, Gen 49:10 Of him came the chief ruler, David first, and, in the fulness of time, Messiah the Prince, Mic 5:2. This honour was secured to Judah, though the birthright was Joseph's; and, having this, he needed not envy Joseph the double portion.

2.The genealogy of the princes of this tribe, the chief family of it (many, no doubt, being omitted), to Beerah, who was head of this clan when the king of Assyria carried them captive, Ch1 5:4-6. Perhaps he is mentioned as prince of the Reubenites at that time because he did not do his part to prevent the captivity.

3.The enlargement of the coasts of this tribe. They increasing, and their cattle being multiplied, they crowded out their neighbours the Hagarites, and extended their conquests, though not to the river Euphrates, yet to the wilderness which abutted upon that river, Ch1 5:9, Ch1 5:10. Thus God did for his people as he promised them: he cast out the enemy from before them by little and little, and gave them their land as they had occasion for it, Exo 23:30.

II.Of the tribe of Gad. Some great families of that tribe are here named (Ch1 5:12), seven that were the children of Abihail, whose pedigree is carried upwards from the son to the father (Ch1 5:14, Ch1 5:15), as that Ch1 5:4, Ch1 5:5, 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. 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 Kg2 15:29, Kg2 15:31. When the judgments of God were ready to break out against them for their wretched degeneracy and apostasy then were they priding themselves in their genealogies, that they were the children of the covenant; as the Jews, in our Saviour's time, who, when they were ripe for ruin, boasted, We have Abraham to our father. Or there might be a special providence in it, and a favourable intimation that though they were, for the present, cast out, they were not cast off for ever. What we design to call for hereafter we keep an inventory of.

Beerah his son - After their separation from the house of David the ten tribes continued to have princes of the tribes; and this continued till the time that Tiglath-pileser carried them captives into Assyria. At that time Beerah was their prince or chief; and with him this species of dominion or precedency terminated. According to the Targum, Beerah was the same as Baruch the prophet.

And Bela the son of Azaz, the son of Shema, the son of Joel,.... The pedigree of Bela, another principal man in the tribe of Reuben, is traced up to Joel the father of Shema; the same with Shemaiah, according to Kimchi and Ben Melech, Ch1 5:4

who dwelt in Aroer; which belonged to the tribe of Gad, and was rebuilt by them, Num 32:34 wherefore Kimchi observes, it may be interpreted, either from Aroer, or on the border of it, Bela dwelt:

even unto Nebo, and Baalmeon; of which See Gill on Num 32:38.