” If you didn’t like lamb, you couldn’t eat a lamb-shaped cookie to make you think of the lamb; if you did, you’d die with rest of the firstborn.” Prove that from scriptures, from the Old Testament scriptures. The instruction was to place THE BLOOD on the doorpost and lintel so the Angel would pass that doorway. In the eating of the Passover lamb then the Israelites’ faith in the Promise to pass over was revealed. FAITH, remember, the core of all of Messiah teaching is FAITH/FAITHING in Him to Give LIFE, to defeat death.
Read the Seder narrative in Exodus 12. It tells you exactly what you have to do, and eating the lamb is on the list.
Catholics hear that passage every Holy Thursday.