These two phrases mean basically the same thing. Yahweh combines them to emphasize that there is no reason to be afraid. (See: [[rc://en/ta/man/translate/figs-parallelism]])
# I have given into your hand the king of Ai ... and his land
Giving them into Israel's hand represents giving Israel victory and control over them. Alternate translation: "I have given you victory over the king of Ai and his people, and I have given you control over his city and his land" (See: [[rc://en/ta/man/translate/figs-metonymy]])
God speaks of what he promises to do as though he had already done it, because he will certainly do it. Alternate translation: "I will certainly give" or "I am giving" (See: [[rc://en/ta/man/translate/figs-pastforfuture]])