Numbers 32:24

21 and every armed man of you will pass over the Jordan before Yahweh, until he has driven out his enemies from before him,

22 and the land is subdued before Yahweh; then afterward you shall return, and be guiltless towards Yahweh, and towards Israel; and this land shall be to you for a possession before Yahweh.

23 But if you will not do so, behold, you have sinned against Yahweh; and be sure your sin will find you out.

24 Build you cities for your little ones, and folds for your sheep; and do that which has proceeded out of your mouth.

25 The children of Gad and the children of Reuben spoke to Moses, saying, Your servants will do as my lord commands.

26 Our little ones, our wives, our flocks, and all our cattle, shall be there in the cities of Gilead;

27 but your servants will pass over, every man who is armed for war, before Yahweh to battle, as my lord says.