Parashat Vayeira: A summary
Here begins the story of the Ten Plagues which G-d put upon the Egyptians not only to effect the release of the Jewish people from bondage, but to show the world that He is the G-d of all creation and history. The first nine plagues are divisible into three groups: 1) the water turning to blood, frogs, lice 2) wild beasts, pestilence/epidemic, boils 3) hail, locust, and darkness.
Rabbi Samson Raphael Hirsch explains that these were punishments measure for measure for afflicting the Jewish people with slavery: 1) The first of each group reduced Egyptians in their own land to the insecurity of strangers. 2) The second of each group robbed them of pride, possessions, and a sense of superiority. 3) The third in each group imposed physical suffering.