John Gill Commentary Ezekiel 21:11

"And it is given to be furbished, that it may be handled: the sword, it is sharpened, yea, it is furbished, to give it into the hand of the slayer." — Ezekiel 21:11 (ASV)

And he has given it to be furbished, that it might be
handled
Either Nebuchadnezzar, or rather God, or the Son of God, prepared and brightened the sword, that it might be handled and made use of, either by the Chaldeans or Romans, to the destruction of the Jews. The Targum is, ``he gave their vengeance to be delivered into the hand of the king of Babylon.''

The sword is sharpened and furbished, to give it into the hand of the
slayer ;
either the king of Babylon, Nebuchadnezzar; or the Roman emperor, Titus Vespasian.