en_tn_condensed/isa/07/18.md

At that time

before the child knows to refuse the evil and choose the good (Isaiah 7:15)

Yahweh will whistle for

"Yahweh will call" or "Yahweh will summon"

for a fly from the distant streams of Egypt, and for a bee from the land of Assyria

Here the armies of Egypt and Assyria are spoken of as if they are insects that will invade the land of Israel. This can be stated as a simile. Alternate translation: "for the armies of Egypt and Assyria, and their soldiers will be everywhere like flies and bees" (See: rc://en/ta/man/translate/figs-metaphorand rc://en/ta/man/translate/figs-simile)