And it shall be for a token upon thine hand, and for frontlets between thine eyes: for by strength of hand the LORD brought us forth out of Egypt.
The firstborn of clean beasts must be sacrificed, and the unclean redeemed with a lamb or destroyed; whatever is unclean by nature, unredeemed, will be destroyed. Your children are polluted too and must be redeemed by blood, that they may belong to the Church of the Firstborn, just as you were delivered by God's hand from the destroying angel.
AI summary
Commenting on Exodus 13:11-16
These ordinances serve as a memorial as plain and constant as tokens worn upon the hand or forehead; they keep the Lord's mighty deliverance before every generation. Each age must reckon itself as having personally escaped Egypt, for they reap the fruits of that wonder and are bound to His covenant by it.
AI summary
It shall be for a token, etc. - See Clarke's note on Exo 13:9.