The connector Therefore opens the verse. It may be rendered “This is why” (New Jerusalem Bible) or “Then” (Revised English Bible). Normally it is an important marker, one that indicates something that is about to happen because of what was described in the previous statement. However, that does not appear to be its function here. Rather, the prophet repeats what was said in verses 9-10. So Good News Translation, Contemporary English Version, Bible en français courant, and Die Bibel im heutigen Deutsch ignore it, and this is a possible option.

I will make the heavens tremble, and the earth will be shaken out of its place: Yahweh will cause the entire world to shake when he comes to punish. This is poetic language. See similar expressions in 2 Sam 22.8 and Psa 18.7. In these two parallel lines the heavens is paired with the earth. For this word pair, see the comments on 1.2. Out of its place may be rendered simply as “thoroughly,” or an ideophone may be used.

At the wrath of the LORD of hosts in the day of his fierce anger: It is Yahweh’s anger that causes this upheaval in the created world. The Hebrew noun rendered wrath is derived from the root meaning “to overflow” or “to cross over.” It appears also in 9.19 (see the comments there). For fierce anger, see Isa 13.9. The double reference to wrath and fierce anger can be combined (so Good News Translation); for example, these two lines may be rendered “when the [burning] anger of Yahweh of hosts is displayed” or “when Yahweh of hosts displays his burning anger.”

Translation examples for this verse are:

• Thus I will cause the heavens to shake and the earth to move when the fierce anger of Yahweh of hosts is displayed.

• This is what I will cause to happen when Yahweh of hosts shows his burning anger: the heavens will tremble and the earth shudder.

Quoted with permission from Ogden, Graham S. and Sterk, Jan. A Handbook on Isaiah. (UBS Helps for Translators). New York: UBS, 2011. For this and other handbooks for translators see here .