18 Gad came that day to David, and said to him, “Go up, build an altar to Yahweh on the threshing floor of Araunah the Jebusite.” 19 David went up according to the saying of Gad, as Yahweh commanded. 20 Araunah looked out, and saw the king and his servants coming on toward him. Then Araunah went out, and bowed himself before the king with his face to the ground. 21 Araunah said, “Why has my lord the king come to his servant?”
David said, “To buy your threshing floor, to build an altar to Yahweh, that the plague may be stopped from afflicting the people.” 22 Araunah said to David, “Let my lord the king take and offer up what seems good to him. Behold, the cattle for the burnt offering, and the threshing instruments and the yokes of the oxen for the wood: 23 all this, king, does Araunah give to the king.” Araunah said to the king, “May Yahweh your God accept you.” 24 The king said to Araunah, “No; but I will most certainly buy it from you for a price. I will not offer burnt offerings to Yahweh my God which cost me nothing.” So David bought the threshing floor and the oxen for fifty shekels of silver.
Matthew Henry's Commentary on 2 Samuel 24:18-24
Commentary on 2 Samuel 24:18-25
(Read 2 Samuel 24:18-25)
God's encouraging us to offer to him spiritual sacrifices, is an evidence of his reconciling us to himself. David purchased the ground to build the altar. God hates robbery for burnt-offering. Those know not what religion is, who chiefly care to make it cheap and easy to themselves, and who are best pleased with that which costs them least pains or money. For what have we our substance, but to honour God with it; and how can it be better bestowed? See the building of the altar, and the offering proper sacrifices upon it. Burnt-offerings to the glory of God's justice; peace-offerings to the glory of his mercy. Christ is our Altar, our Sacrifice; in him alone we may expect to escape his wrath, and to find favour with God. Death is destroying all around, in so many forms, and so suddenly, that it is madness not to expect and prepare for the close of life.