'Buy' in the Bible

Then Araunah said, "Why has my lord the king come to his servant?" David said, "To buy from you the threshing floor, to build an altar to Yahweh who brought a halt to the plague on the people."

Then the king said to Araunah, "No, but {I will certainly buy} it from you for a price; I don't want to offer to Yahweh my God burnt offerings that cost me nothing." So David bought the threshing floor and the cattle for fifty shekels of silver.