66 The Hebrew text reads “with terrifying power,” or “with a crash.” מַעֲרָצָה (ma’aratsah, “terrifying power” or “crash”) occurs only here. Several have suggested an emendation to מַעֲצָד (ma’atsad, “ax”) parallel to “ax” in v. 34; see מַעֲצָד and H. Wildberger, Isaiah, 1:. As in vv. 12 (see the note there) and 18, the Assyrians are compared to a tree/forest in vv. 33–34.
67 Heb “the exalted of the height.” This could refer to the highest branches (cf. ) or the tallest trees (cf. , ).
68 The Hebrew text has, “and Lebanon, by/as [?] a mighty one, will fall.” The translation above takes the preposition בְּ (bet) prefixed to “mighty one” as indicating identity, “Lebanon, as a mighty one, will fall.” In this case “mighty one” describes Lebanon. (In Ezek 17:23 and Zech 11:2 the adjective is used of Lebanon’s cedars.) Another option is to take the preposition as indicating agency and interpret “mighty one” as a divine title (see Isa 33:21). One could then translate, “and Lebanon will fall by [the agency of] the Mighty One.”

In other versions

Behold, the Lord God of hosts

will lop the boughs with terrifying power;

the great in height will be hewn down,

and the lofty will be brought low.

He will cut down the thickets of the forest with an axe,

and Lebanon will fall by the Majestic One.

See, the Lord, the Lord Almighty,

will lop off the boughs with great power.

The lofty trees will be felled,

the tall ones will be brought low.

He will cut down the forest thickets with an ax;

Lebanon will fall before the Mighty One.

Look, the Lord God of Armies

will chop off the branches with terrifying power,

and the tall trees will be cut down,

the high trees felled.

He is clearing the thickets of the forest with an ax,

and Lebanon with its majesty will fall.

But look! The Lord, the Lord of Heaven’s Armies,

will chop down the mighty tree of Assyria with great power!

He will cut down the proud.

That lofty tree will be brought down.

He will cut down the forest trees with an ax.

Lebanon will fall to the Mighty One.

Look! The Lord Yahweh of hosts is about to lop off the branches with great power,

and the towering trees will be felled,

and the tall trees will be brought low.

And he will cut down the thickets of the forest with the axe,

and Lebanon will fall by the mighty one.

Behold, the Lord, the Lord of hosts,

Shall lop the bough with terror:

And the high ones of stature shall be hewn down,

And the haughty shall be humbled.

And he shall cut down the thickets of the forest with iron,

And Lebanon shall fall by a mighty one.

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