Exodus 10:4
If you refuse to let my people go, I will bring locusts into your country tomorrow. The eighth plague is the first to announce not only what it will do but when: tomorrow. The announcement of tomorrow's locusts gives Pharaoh one night to change course — one more opportunity added to the seven already given. The locust in the ancient Near East was the most feared natural disaster after famine — the two were often caused by the same event, since locusts devoured the crops that prevented famine. Joel 1–2 uses the locust plague as its central image for divine judgment: a day of darkness and gloom, a great and mighty army. The locusts of Exodus 10 stand behind Joel's vision as the historical template for eschatological judgment. What God did to Egypt through locusts, He will do to the nations through the locust-like creatures of Revelation 9:3.