Exodus 13:14-15

EJ2000(i) 14 And it shall be when thy son asks thee in time to come, saying, What is this? Thou shalt say unto him, With a strong hand the LORD brought us out of Egypt, from the house of slavery; 15 and it came to pass when Pharaoh was hardening himself to not let us go that the LORD slew all the firstborn in the land of Egypt from the human firstborn to the firstborn of the beast; therefore, I sacrifice to the LORD every male that opens the womb, and I ransom every firstborn of my sons.