Exodus 13:13-16

“Redeem every firstborn child among your sons. When the time comes and your son asks you, ‘What does this mean?’ you tell him, ‘GOD brought us out of Egypt, out of a house of slavery, with a powerful hand. When Pharaoh stubbornly refused to let us go, GOD killed every firstborn in Egypt, the firstborn of both humans and animals. That’s why I make a sacrifice for every first male birth from the womb to GOD and redeem every firstborn son.’ The observance functions like a sign on your hands or a symbol on the middle of your forehead: GOD brought us out of Egypt with a powerful hand.”