Isaiah 7:4

4 Say to him, ‘Be careful, keep calm and don’t be afraid. Do not lose heart because of these two smoldering stubs of firewood—because of the fierce anger of Rezin and Aram and of the son of Remaliah.

Read Isaiah 7:4 Using Other Translations

And say unto him, Take heed, and be quiet; fear not, neither be fainthearted for the two tails of these smoking firebrands, for the fierce anger of Rezin with Syria, and of the son of Remaliah.
And say to him, 'Be careful, be quiet, do not fear, and do not let your heart be faint because of these two smoldering stumps of firebrands, at the fierce anger of Rezin and Syria and the son of Remaliah.
Tell him to stop worrying. Tell him he doesn’t need to fear the fierce anger of those two burned-out embers, King Rezin of Syria and Pekah son of Remaliah.

What does Isaiah 7:4 mean?

John Gill's Exposition of the Bible
Isaiah 7:4

And say unto him, take heed, and be quiet
Or "keep" thyself, not within the city, and from fighting with his enemies, but from unbelief, fear, and dread; or, as the Septuagint version, "keep" thyself, "that thou mayest be quiet" F1; be easy, still, and silent, and see the salvation of God: the Jewish writers interpret the first word of resting and settling, as wine upon the lees: see ( Jeremiah 48:11 ) : fear not;
this explains the former: neither be fainthearted;
or "let thy heart soft" F2, and melt like wax, through dread and diffidence: for the two tails of these smoking firebrands:
meaning the two kings of Syria and Israel: and so the Targum,

``for these two kings, who are as smoking firebrands;''
a metaphor used to express the weakness of these princes, their vain wrath and impotent fury, and the short continuance of it; they being like to firebrands wholly burnt and consumed to the end; a small part remaining, which could not be laid hold upon to light fires or burn with, and that only smoking, and the smoke just ready to vanish. For the fierce anger of Rezin with Syria, and of the son of
Remaliah;
this shows who are meant by the two firebrands, Rezin king of Syria, and Pekah king of Israel; and what by the smoke of them, their fierce anger; which, though it seemed to threaten with utter destruction, in the opinion of Ahaz and his court, was only like the smoke of a firebrand burnt to the end, weak and vanishing.
FOOTNOTES:

F1 (jqvhw rmvh) (fulaxai) , Sept.; "observa ut sis quieto animo", Vatablus.
F2 (Kry la) "ne mollescas", Junius & Tremellius, Piscator.
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