Deuteronomy 3:18-22 - Instructions To The Transjordanian Tribes
18 Then I gave them the following instructions: 'Jehovah our God gave you the land east of the Jordan to occupy. Now arm your fighting men and send them across the Jordan ahead of the other tribes of Israel, to help them occupy their land. 19 Your wives, children, and livestock, for you have a lot of livestock, will remain behind in the towns I assigned to you. 20 Help the other Israelites until they occupy the land Jehovah is giving them west of the Jordan and until Jehovah lets them live there in peace, just as he has done here for you. After that, you may return to the land I assigned to you.'
21 I also gave Joshua this command: 'You have seen with your own eyes everything Jehovah your God has done to these two kings. Jehovah will do the same to all of the kingdoms on the other side of the Jordan River where you are going. 22 Do not be afraid of them. For Jehovah your God fights for you.'