Numbers 32:20-22

20 So a Moses said to them, “If you will do this, if you will take up arms to go before the  Lord for the war, 21 and every armed man of you will pass over the Jordan before the  Lord, until he has b driven out his enemies from before him 22 and the land is subdued before the  Lord; then after that you shall return and be free of obligation to the  Lord and to Israel, and c this land shall be your possession before the  Lord.
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