2 Samuel 24:22-24

22Then Araunah said to David, “Let my lord the king take and offer up what seems good in his eyes. Look here, the oxen for the burnt offering, as well as the threshing sledges and the ox yokes for the wood.

23All this Araunah gives to the king.” Araunah said further to the king, “May Adonai your God accept you.”

24But the king said to Araunah, “No, but I will surely buy it from you at a price. I will not offer burnt offerings to Adonai my God that cost me nothing.” So David bought the threshing floor and the oxen for 50 shekels of silver.