2 Samuel 24:22-24

22Araunah said to David, “Let my lord the king take and offer up whatever seems good to him. Look, here are oxen for the burnt offering, and threshing sledges and the yokes of the oxen for the wood.

23All of this, O king, Araunah gives to the king.” And Araunah said to the king, “May the Lord your God be favorable to you.”

24But the king said to Araunah, “No, but I will certainly buy it from you for a price. I will not offer burnt offerings to the Lord my God which cost me nothing.” So David purchased the threshing floor and the oxen for fifty shekels of silver.