In this verse the watchmen of Jerusalem see the LORD returning (or the messenger coming) and are happy. Bible en français courant uses the conjunction “therefore” to link this verse with the previous one.

Hark, your watchmen lift up their voice is literally “Voice/sound of your watchmen! They raise a voice/sound.” Grammatically speaking, the initial noun phrase in Hebrew is an interjection. But the overall sense of this line is clear enough. It describes the watchmen of Jerusalem, perhaps on the city wall, calling out when they see that Yahweh himself (or the messenger) is approaching. Instead of rendering the Hebrew interjection at the beginning of this verse as Hark, New Revised Standard Version has “Listen!” (also New International Version). The pronoun your is feminine singular in Hebrew, so it refers to Jerusalem again, as in the previous verse. Good News Translation makes it explicit that the watchmen are guarding the city. Lift up their voice means the watchmen call out loudly to the people in the city (see the comments on this expression at 40.9 and 42.2).

Together they sing for joy is better translated “together they shout for joy.” The Hebrew verb rendered sing for joy means simply “to shout” (see the comments on 12.6). Only the wider context suggests that this shouting is joyous. Like Revised Standard Version, most versions add the idea of joy here. The adverb together points to the fact that many guards are joyfully shouting at the same time.

For eye to eye they see: The Hebrew particle ki rendered for is a logical connector here. Good News Translation leaves it implied, but most versions express it explicitly. Eye to eye they see renders an unusual idiom in Hebrew (compare Jer 32.4; 34.3). The more common idiom is “see face to face” (see, for example, Gen 32.30; Jdg 6.22), which indicates physical nearness or could point to a very close relationship. Most commentators understand eye to eye to mean that the watchmen see something “with their own eyes” (Good News Translation, New International Version, Revised English Bible, New Jerusalem Bible, Bible en français courant). On the other hand, New Jewish Publication Society’s Tanakh renders this whole line as “For every eye shall behold.”

The return of the LORD to Zion: It is not clear whether the watchmen see the messenger bringing the news that Yahweh is coming back to Zion, or whether they see Yahweh himself returning to Zion (compare 40.3). Most commentators regard this line as a poetic description of the latter sense. The LORD’s return to Jerusalem implies a return of his people to the city. This is made clear in a passage such as 40.10-11 (see the comments there).

Translation examples for this verse are:

• Listen, your guards raise the shout,
they all call out with joy,
because everybody sees the LORD returning to Zion.

• Listen, your guardsmen call out,
with joy they shout together;
with their own eyes they see the LORD coming back to Zion.

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 .