Joshua 22:24-25

We built that altar because we were worried. Someday your descendants might tell our descendants, “The LORD made the Jordan River the boundary between us Israelites and you people of Reuben and Gad. The LORD is Israel's God, but you're not part of Israel, so you can't take part in worshiping the LORD.” Your descendants might say that and try to make our descendants stop worshiping and obeying the LORD.