Charles Ellicott Commentary Isaiah 22:8

"And he took away the covering of Judah; and thou didst look in that day to the armor in the house of the forest." — Isaiah 22:8 (ASV)

And he discovered the covering of Judah. — that is, Jehovah removed the veil which until then had hidden the approaching danger from the eyes of the inhabitants, and laid bare their weakness to those of the invaders. The verbs which in the English version are in the past tense are really in a kind of prophetic present, painting the future as if actually passing before the prophet’s gaze.

The armour of the house of the forest. — More fully (as in 1 Kings 7:2; 1 Kings 10:17), the house of the forest of Lebanon, which appears to have been used as an arsenal, and to which the people now turn as their chief resource.