The ten plagues are divided into two parshiot - the first seven in parshat Va'era and the last three in parshat Bo. Is this merely a division of convenience, or is there an important distinction between these two groups of plagues? By closely examining the text surrounding each of the final three plagues, one can gain an understanding of the shift in Moshe's mission. God wants Moshe's personal involvement, and he switches Moshe's role from the representative of the Jewish people, speaking in God's name, to the representative of God Himself.

Courtesy of the Virtual Beit Midrash, Yeshivat Har Etzion