ה֥וֹי אַשּׁ֖וּר שֵׁ֣בֶט אַפִּ֑י וּמַטֶּה־ה֥וּא בְיָדָ֖ם זַעְמִֽי׃
O Asshur, the rod of Mine anger, In whose hand as a staff is Mine indignation!
Rashi on Isaiah
Woe that I made Assyria the rod of My wrath with which to chastise My people.
Ibn Ezra on Isaiah
הוי Oh. Sign of the vocative.1See I. E. on 1:4, and Note 13.
Rashi on Isaiah
and...a staff is My fury in the hands of the people of Assyria.