2 Samuel_24:24 But the king replied to Araunah, “No, I insist on paying you for it. I will not sacrifice to the LORD my God burnt offerings that cost me nothing.” So David bought the threshing floor and the oxen and paid fifty shekels of silver for them.
The farmer wanted to give these things to David but David insisted upon paying a good price for it. His reason was that he could not offer to God things that cost him nothing. This is the mind of real believers. We cannot buy our salvation with works and personal sacrifices but we can take up the cost of being in the world but not of it. We can take on the cost of devotion to God in a world devoted to pleasure. We can take on the cost of leaving behind stuff that just slows down our progress towards being like Jesus. We can count the cost and decide that Jesus is worth those little sacrifices that are necessary to be an every day believer.