1 Chronicles 21:26
And David built there an altar unto the LORD, and offered burnt offerings and peace offerings, and called upon the LORD; and he answered him from heaven by fire upon the altar of burnt offering. And David built there an altar unto the LORD, and offered burnt offerings and peace offerings, and called upon the LORD; and he answered him from heaven by fire upon the altar of burnt offering.
The altar stood on the threshing floor of Ornan, also called Araunah, on Mount Moriah, the very ground where the temple was afterward built. After confessing his sin in numbering Israel, David built an altar there and offered burnt offerings and peace offerings and called upon the Lord. The Lord answered him from heaven by fire upon the altar of burnt offering, accepting the sacrifice by sending fire to consume it, and the Lord was entreated for the land.
That sacrifice and that fire turned aside the avenging sword of the destroying angel, the plague was stopped, and the angel was commanded to stop the destruction. The answer by fire marked the spot as consecrated holy ground, a place to meet God and renew vows of allegiance to Him, and it later became the site of Solomon's temple. The same place joins David's altar with Abraham's altar built there to offer his son, and with the worship afterward offered there.
The fire from heaven turning aside the sword is a fitting symbol of the Saviour's sacrifice and mediation for guilty people.