What does Exodus 10:5 mean?
Moses and Aaron have predicted a plague of locusts (Exodus 10:4) if Pharaoh refuses to free the Hebrew slaves (Exodus 10:3). Locusts are a form taken on by grasshoppers under certain conditions. Compared to typical grasshoppers, locusts are more aggressive, hungrier, and driven to gather close to each other. When their numbers rise, locust swarms can ruin crops by quickly eating everything before flying away to do the same thing again.The plague threatened on Egypt is epic: worse than anything ever seen before (Exodus 10:6). The nation has already been devastated by a hailstorm that crushed crops and destroyed trees (Exodus 9:24–25). Everything that recovered from hailstones will be eaten by swarming insects. There will be so many locusts that a person won't be able to see the ground. Fields and houses will be completely overrun.
Ancient people knew well what locusts could do. Pharaoh's advisors will react to this threat by begging their king to negotiate with Moses (Exodus 10:7).