rsv Exodus:13:14-15
rsv@Exodus:13:14 @ And when in time to come your son asks you, `What does this mean?' you shall say to him, `By strength of hand the LORD brought us out of Egypt, from the house of bondage.
rsv@Exodus:13:15 @ For when Pharaoh stubbornly refused to let us go, the LORD slew all the first-born in the land of Egypt, both the first-born of man and the first-born of cattle. Therefore I sacrifice to the LORD all the males that first open the womb; but all the first-born of my sons I redeem.'