Isaiah 18:2-3

2which 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. 3All 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.