Deuteronomy 3:21 in the King James Version
And I commanded Joshua at that time, saying, Thine eyes have seen all that the LORD your God hath done unto these two kings: so shall the LORD do unto all the kingdoms whither thou passest.
Context
20 until the LORD gives rest to your brothers, as to you, and they also possess the land which the LORD your God gives them beyond the Jordan. Then you shall each return to his own possession, which I have given you.”
21 I commanded Joshua at that time, saying, “Your eyes have seen all that the LORD your God has done to these two kings. So shall the LORD do to all the kingdoms where you go over.
22 You shall not fear them; for the LORD your God himself fights for you.”