1 Chronicles 21:27

And the LORD commanded the angel; and he put up his sword again into the sheath thereof.

The Lord commanded the destroying angel to put his avenging sword back into its sheath, staying the destruction. That command was given at Ornan's threshing floor in Jerusalem. That threshing floor was on Mount Moriah, the consecrated spot later marked as holy as the ground where the temple was built.

The sheathing came after David's repentance and sacrifice were accepted. He offered burnt offerings and peace offerings to stop the sword, which God accepted and answered by fire from heaven. The accepted sacrifice turned aside the angel's destruction. In this way it stopped the plague against Jerusalem.

That turning aside of the sword by sacrifice was a symbol foreshadowing the Saviour's sacrifice and mediation for guilty people. The stopping of the plague shows that God still had compassion on Israel despite its rebellion.