Signal

A wartime signal in the prophets is something raised to be seen and sounded to be heard, so that scattered onlookers can converge on a single moment. The umbrella sits beside the entries on banners and trumpets, but its own occurrence is narrower — one verse where both signs run together as a paired summons.

Ensign and Trumpet

Isaiah's oracle calls the world's onlookers to watch and listen at the same instant: "All you⁺ inhabitants of the world, and you⁺ who stay on the earth, when an ensign is lifted up on the mountains, see⁺; and when the trumpet is blown, hear⁺" (Isa 18:3). The lifted ensign carries the visual signal; the blown trumpet carries the audible one. Both are addressed in the plural to the whole inhabited earth. The verse compresses signaling into its two complementary channels — sight and sound — and treats the response as obligatory: the imperatives "see⁺" and "hear⁺" leave no room for the bystander to ignore the cue.