Albert Barnes Commentary Ezekiel 38:16

"and thou shalt come up against my people Israel, as a cloud to cover the land: it shall come to pass in the latter days, that I will bring thee against my land, that the nations may know me, when I shall be sanctified in thee, O Gog, before their eyes." — Ezekiel 38:16 (ASV)

I shall be sanctified in thee - I shall be shown to be holy and just in avenging Myself on My enemy.