2 Samuel 24:24-25

24:24 But the king said to Araunah, “No, I insist on buying it from you! I will not offer to the Lord my God burnt sacrifices that cost me nothing.”

So David bought the threshing floor and the oxen for fifty pieces of silver. ¹  24:25 Then David built an altar for the Lord there and offered burnt sacrifices and peace offerings. And the Lord accepted prayers for the land, and the plague was removed from Israel.

¹ tn Heb “fifty shekels of silver.” This would have been about 20 ounces (568 grams) of silver by weight.