The sun shall be turned to darkness, and the moon to blood: In the sky the portents may be eclipses of the sun and the moon (see the comments on verse 10). At such times the sun becomes completely black and the moon appears to be dark red, the color of blood. Clouds of dust or smoke in the air could also cause these portents to happen, even when no eclipse occurs. In many languages translators will prefer to follow the Good News Translation model here, which turns the metaphor of blood into a simile, saying “The sun will be darkened, and the moon will turn red as blood.”

The events both on earth and in the sky will take place before the great and terrible day of the LORD comes. This is the first time the day of the LORD is clearly identified in this section (see the comments on this expression at 1.15). The adjectives great and terrible describe the same day in verse 11, so they should be rendered in the same way here in order to show that these verses are related. Since the LORD is speaking here, some translators may want to render this whole clause as “before that great and terrible day, when I, the LORD, come” (similarly Contemporary English Version, Die Bibel im heutigen Deutsch).

In some languages it may be better to mention the portents occurring in the sky with the sky, and those occurring on earth with the earth. This will require combining verses 30 and 31, and restructuring their parts. A model that does this is:

• And I will give warning signs on the earth:
blood and fire and columns of smoke.
And I will also give warning signs in the heavens:
the sun shall be turned to darkness,
and the moon to blood.
All this will happen before the great and terrible day of the LORD comes.

The following model keeps the chiastic order, but it places the last line of verse 31 first:

• Before the great and terrible day of the LORD comes,
I will give warning signs in the heavens and on the earth.
The warning signs on the earth will be
blood and fire and columns of smoke.
The warning signs in the heavens will be
that the sun shall be turned to darkness,
and the moon to blood.

Quoted with permission from de Blois, Kees & Dorn, Louis. A Handbook on Joel. (UBS Helps for Translators). Miami: UBS, 2020. For this and other handbooks for translators see here .