The tribes of Reuben and Gad had enormous herds, and when they saw the conquered territory east of the Jordan, they wanted to stay. The Targum's version of (Numbers 32) captures Moses's fury at their request in sharper terms than the Torah. "Shall your brethren go to the war, and you sit down here?" he demanded. "Why should you enfeeble the will of the sons of Israel from going over to the land which the Lord has given to them?"
Moses connected their selfishness to Israel's greatest historical trauma. "So did your fathers when I sent them from Rekem Giah to survey the land"—the Targum's name for Kadesh Barnea. The spies "went up to the brook of Ethkela, and saw the land, but enfeebled the will of Israel's heart." The same verb—enfeeble—links the two generations. Reuben and Gad were repeating the sin of the spies, choosing comfort over covenant.
God's oath in response was absolute. The entire generation that left Egypt, everyone twenty years and older, would die in the wilderness "because they have not fully walked according to My fear." Only Caleb and Joshua survived, "for they have fully walked after the fear of the Lord." Moses warned the two tribes: "You are risen up after your fathers, disciples of wicked men, to increase yet the anger of the Lord against Israel."
The tribes proposed a compromise. They would build fortified towns for their families and sheepfolds for their flocks, then march armed at the front of Israel's army "until we have brought them into their place." The Targum emphasizes that these were not rear-guard volunteers—they would lead the invasion, not follow it.
The rebuilt cities are listed with their Targum names, including details the Torah omits. The sons of Reuben rebuilt "the city of the two streets paved with marble which is Beresha" and "the place of the sepulchre of Moses"—a striking reference to Moses's future burial site being prepared by the very tribe that had nearly provocation a second wilderness sentence. They also rebuilt "the city of Balak, destroying out of it the idol of Peor, in the house of his high places," purging the territory of the cult that had nearly destroyed Israel at Shittim.