Gregory of Nyssa
The passage from Exodus 10:21 can also be understood as symbolic of the ashes from the furnace, which inflict grievous wounds upon the Egyptians. These ashes, associated with the furnace, represent the consequences of the unquenchable fire of Gehenna, which is reserved solely for those who conduct their lives in the manner of the Egyptians, that is, those who consistently live in sin and reject the outstretched hands of Christ. However, if a true Israelite, a descendant of Abraham, lives in a manner that reflects Abraham's virtues, demonstrating his commitment to God's chosen, he will be spared from this torment of the abyss. Furthermore, the outstretched hands of Moses indicate a hope for those who resemble the Egyptians; in the future, they may find a remedy for their suffering and a means of liberation from punishment.