Leviticus 11:22-23

Just to recap quickly, they must fly, they must leap, they must have jointed legs above their feet, and creep on all fours in order to be clean. The only insects that fit those qualifications are grasshoppers and locusts.

God repeats that twice to make sure we understand that. The identity of these four locusts is uncertain. This is as far as their specific types, but they are all of the locust family or grasshopper family. They are sure to be different kinds of locusts. Anyway, crickets are not clean because technically they do not fly. They prefer to creep and they eat other insects, compared with locusts and grasshoppers, which are herbivores. So the crickets do not prefer grass and things like that— plants. But locusts and grasshoppers prefer green grass, being herbivores, and also they are out during the day, whereas crickets come out at dusk and dawn so they are creepy crawlers. They do not truly fly.