2 Samuel 8:10

8:10 he sent his son Joram to King David to extend his best wishes and to pronounce a blessing on him for his victory over Hadadezer, for Toi had been at war with Hadadezer. He brought with him various items made of silver, gold, and bronze.

2 Samuel 21:4

21:4 The Gibeonites said to him, “We have no claim to silver or gold from Saul or from his family, nor would we be justified in putting to death anyone in Israel.” David asked, “What then are you asking me to do for you?”

2 Samuel 24:24

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.