Isaiah 18, The Kushite Empire and a Banner

After prophesying about Damascus and the northern kingdom, Isaiah turns to Egypt.

Isaiah 18:1-2, Prophecy against Cush

Woe to the land of whirring wings

    along the rivers of Cush,

which sends envoys by sea

    in papyrus boats over the water.

Go, swift messengers,

to a people tall and smooth-skinned,

    to a people feared far and wide,

an aggressive nation of strange speech,

    whose land is divided by rivers.

The prophecy does not open with  massa' ("burden", "oracle") but with hoy, "Woe!", presumably a warning of doom. The Hebrew tslatsal is translated "whirring wings"; that Hebrew word is intended to sound like the zzzz buzzing of many insects among the Nile wetlands (Grogan, p. 122.)

Cush, with its papyrus boats, often refers to Ethiopia but here, more broadly, to the empire of Egypt. The Twenty-fifth Dynasty of Egypt (744-656 BC) originated in the Kingdom of Kush and it is probably this dynasty that is referred to here. That empire would eventually fall to the Assyrians.

Motyer argues that this passage represents "frantic diplomacy" by Egypt to organize an alliance against Assyria during Isaiah's time but, more globally, is a description of "busy-busy world confidence" in diplomacy and national security.

Isaiah 18:3, A raised banner

All you people of the world,

    you who live on the earth,

when a banner is raised on the mountains,

    you will see it,

and when a trumpet sounds,

    you will hear it.

Isaiah announces a banner visible to the world. There is an emphasis on the banner's public appearance as something both visible and audible; it will not be missed.

Isaiah 18:4-6, Harvest left for birds and animals

This is what the LORD says to me:

    “I will remain quiet and will look on from my dwelling place,

like shimmering heat in the sunshine,

    like a cloud of dew in the heat of harvest.”

For, before the harvest, when the blossom is gone

    and the flower becomes a ripening grape,

he will cut off the shoots with pruning knives,

    and cut down and take away the spreading branches.

They will all be left to the mountain birds of prey

    and to the wild animals;

the birds will feed on them all summer,

    the wild animals all winter.

YHWH looks down on mankind, as destruction comes to Egypt before harvest. The destroying army leaves debris that feeds the birds and wild animals. Motyer sees here the "local" prophecy of the Assyrian dead described in Isaiah 37:36-37 and 2 Kings 19:35-36. But like many prophecies, there is (says Motyer) a future global prophecy regarding a final judgment.

Isaiah 18:7, Gifts to Zion

At that time gifts will be brought to the LORD Almighty

from a people tall and smooth-skinned,

    from a people feared far and wide,

an aggressive nation of strange speech,

    whose land is divided by rivers—

the gifts will be brought to Mount Zion, 

the place of the Name of the LORD Almighty.

But a people "tall and smooth-skinned" will bring gifts to YHWH, people of "strange speech", bringing gifts to Mount Zion. As in other passages, there is a future day in which Zion will be the center of worship of people from many lands. The process of judgment and then salvation will be repeated in the next chapter.