God sent an angel to Jerusalem to destroy it: and as he was about to destroy, Yahweh saw, and he repented him of the evil, and said to the destroying angel, It is enough; now stay your hand. The angel of Yahweh was standing by the threshing floor of Ornan the Jebusite.
"Here, by divine command, is to be the site of the temple. It is a gift not from Ornan but from God. The grace of God, in giving this to His people as the place where ark and altar are to be brought together, is a thing to be wondered at." [Note: Wilcock, p. 95.] 