13 Heb “when” (so , , ); “after”; “once.”
14 The Hebrew term translated “sovereign master” here is אֲדֹנָי (’adonai).
15 The word refers elsewhere to vomit (Isa 28:8) and fecal material (Isa 36:12). Many English versions render this somewhat euphemistically as “filth” (e.g., , , ). Ironically in God’s sight the beautiful jewelry described earlier is nothing but vomit and feces, for it symbolizes the moral decay of the city’s residents (cf. “moral filth”).
16 See 1:21 for a related concept.
17 Heb “by a spirit of judgment and by a spirit of burning.” The precise meaning of the second half of the verse is uncertain. רוּחַ (ruakh) can be understood as “wind” in which case the passage pictures the Lord using a destructive wind as an instrument of judgment. However, this would create a mixed metaphor, for the first half of the verse uses the imagery of washing and rinsing to depict judgment. Perhaps the image would be that of a windstorm accompanied by heavy rain. רוּחַ can also mean “spirit,” in which case the verse may be referring to the Lord’s Spirit or, more likely, to a disposition that the Lord brings to the task of judgment. It is also uncertain if בָּעַר (ba’ar) here means “burning” or “sweeping away, devastating.”
18 Heb “over all the place, Mount Zion.” Cf. “Jerusalem”; “the whole city.”
19 Heb “a cloud by day, and smoke, and brightness of fire, a flame by night.” Though the accents in the Hebrew text suggest otherwise, it might be preferable to take “smoke” with what follows, since one would expect smoke to accompany fire. The imagery of the cloud by day and fire by night recalls the days of Moses, when a cloud and fire were tangible reminders that the Lord was guiding and protecting his people (Exod 13:21–22; 14:19, 24). In the future age envisioned in Isa 4, the Lord’s protective presence will be a reality.
20 Heb “indeed (or “for”) over all the glory, a canopy.” This may allude to Exod 40:34–35, where a cloud overshadows the meeting tent as it is filled with God’s glory.

In other versions

ESVEnglish Standard Version

when the Lord shall have washed away the filth of the daughters of Zion and cleansed the bloodstains of Jerusalem from its midst by a spirit of judgment and by a spirit of burning. Then the Lord will create over the whole site of Mount Zion and over her assemblies a cloud by day, and smoke and the shining of a flaming fire by night; for over all the glory there will be a canopy.

NIVNew International Version (2011)

The Lord will wash away the filth of the women of Zion; he will cleanse the bloodstains from Jerusalem by a spirit of judgment and a spirit of fire. Then the Lord will create over all of Mount Zion and over those who assemble there a cloud of smoke by day and a glow of flaming fire by night; over everything the glory will be a canopy.

CSBChristian Standard Bible

when the Lord has washed away the filth of the daughters of Zion and cleansed the bloodguilt from the heart of Jerusalem by a spirit of judgment and a spirit of burning. Then the Lord will create a cloud of smoke by day and a glowing flame of fire by night over the entire site of Mount Zion and over its assemblies. For there will be a canopy over all the glory,

NLTNew Living Translation

The Lord will wash the filth from beautiful Zion

and cleanse Jerusalem of its bloodstains

with the hot breath of fiery judgment.

Then the Lord will provide shade for Mount Zion

and all who assemble there.

He will provide a canopy of cloud during the day

and smoke and flaming fire at night,

covering the glorious land.

LEBThe Lexham English Bible

when the Lord has washed away the filth of the daughters of Zion

and cleansed the blood of Jerusalem from her midst

by a spirit of judgment

and by a spirit of burning.

Then Yahweh will create over all of the site of Mount Zion

and over her assembly a cloud by day

and smoke and the brightness of flaming fire by night.

Indeed, over all the glory there will be a canopy,

KJV 1900King James Version

When the Lord shall have washed away the filth of the daughters of Zion,

And shall have purged the blood of Jerusalem from the midst thereof

By the spirit of judgment, and by the spirit of burning.

And the Lord will create upon every dwelling place of mount Zion,

And upon her assemblies,

A cloud and smoke by day,

And the shining of a flaming fire by night:

For upon all the glory shall be a defence.

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