Numbers 32:17

32:17 but we will maintain ourselves in armed readiness and go before the Israelites until whenever we have brought them to their place. Our descendants will be living in fortified towns as a protection against the inhabitants of the land.

Numbers 32:29

32:29 Moses said to them: “If the Gadites and the Reubenites cross the Jordan with you, each one equipped for battle in the Lord’s presence, and you conquer the land, then you must allot them the territory of Gilead as their possession.