New Defender's Study Bible Notes
10:4 locusts into thy coast. The eighth plague was the greatest horde of devouring locusts ever seen in Egypt (Exodus 10:14). All the vegetation not destroyed by the hail was eaten by the locusts (Exodus 10:15). The goddess Isis was supposed to be Egypt’s protectrix against locusts, but she failed miserably.
10:13 the east wind. The day and night of heavy wind would indicate that God brought the locusts from some distant land. This should have testified that God was Lord over all the earth, not just Egypt and Israel.
10:22 thick darkness. This could hardly have been merely a dust storm, for it was not just darkness, but thick darkness, so thick that the Egyptians were helpless for three days (Exodus 10:23). The darkness did not extend into the land of Goshen, where the Israelites dwelt.
10:23 saw not one another. The chief deity of Egypt was Ra, the sun god, so this miracle clearly demonstrated that the God of Israel was greater than all the gods of Egypt. In fact, each of the ten plagues seemed designed to insult one of the many “gods” of the polytheistic Egyptians.