Numbers 32:38
And Nebo, and Baal-meon, (their names being changed,) and Shibmah: and gave other names unto the cities which they builded. And Nebo, and Baal-meon, (their names being changed,) and Shibmah: and gave other names unto the cities which they builded.
The verse belongs to Moses' dealing with the two and a half tribes that proposed to remain on the east side of the Jordan as Israel approached the promised land, when some sought to settle east of the Jordan and beyond the Jordan. It is part of the account of the settlement of the two and one-half tribes east of the Jordan. In that setting Moses addressed to them the solemn admonition to be sure sin will find out the sinner, because he feared they would depart from God and fail in the fulfilment of their solemn vows, knowing such failure would bring upon themselves lasting sorrow and final ruin.
The tribes' choice to settle east serves as a warning against staying back while others go forward. The children of Reuben changed the names formerly called Nebo and Baal-meon because those names belonged to heathen idols. The episode is presented for its warning about turning from God and breaking vows rather than to explain the city names or their changes.