"Tell your children and grandchildren how I dealt harshly with the Egyptians and how I performed my signs among them, and that you may know that I am the LORD." (Exodus 10:2)
God tells Moses: I have hardened Pharaoh's heart so that I may perform these signs among them and so that you may tell your children and grandchildren what I did. The purpose of the Exodus is generational transmission: the story is to be told, retold, and retold again so that every generation knows who the LORD is from the witness of the preceding one. Tell your children and grandchildren how I dealt harshly with the Egyptians and how I performed my signs among them, and that you may know that I am the LORD. This is the theology of the Passover Seder in miniature: the great acts of God are not merely historical records but living testimony passed from mouth to ear across generations.
The eighth plague: locusts cover the face of the ground until it is black, devouring everything the hail has left. Pharaoh's officials plead with him: do you not yet realise that Egypt is ruined? Pharaoh negotiates again: only the men may go, not the women and children. Moses refuses. The locusts are sent; they devour everything. Pharaoh confesses sin again and asks forgiveness; the locusts are removed. His heart hardens. The ninth plague: thick darkness covers Egypt for three days, so dark it can be felt. But all the Israelites have light in their dwellings. Pharaoh says: go, leave me, but your flocks must stay. Moses refuses: not a hoof is to be left behind. Pharaoh is furious: get out of my sight. The day you see my face you will die.
Brothers and sisters, tell your children and grandchildren what God did. The transmission of faith is not automatic. It requires deliberate, repeated narration: this is what God did for us, this is what he has done in my life, this is the story of his acts that you inherit. What are you telling? What are your children and grandchildren hearing from you about who God is?
Lord God, you performed your signs so that every generation would know that you are the LORD. Give us the words to tell your story to those who come after us. Let no generation inherit silence where testimony should have been. Through Christ our Lord. Amen.