On the night that would change everything, God told the Israelites to paint blood on their doorframes. But where exactly? On the inside of the doorposts and lintel, or on the outside? The Mekhilta records a debate that reveals two fundamentally different understandings of what the blood was for.
Rabbi Yishmael argues the blood went on the inside. His proof is devastating in its simplicity. God says, "And I will see the blood" (Exodus 12:13). If an omniscient God needs to "see" the blood, it means the blood is not for public display. It is hidden on the interior of the doorframe, visible only to the One who passes through Egypt that night. "Blood which is seen by Me," Rabbi Yishmael concludes, "and not by others."
This reading transforms the entire Passover narrative. The blood was not a flag or a signal meant to warn off a blind destructive force. It was an intimate act of faith between each Israelite household and God. No Egyptian neighbor would see it. No one walking down the street would know which houses were marked. The blood was a private covenant — painted in a place only God would look.
The theological implication is profound. God does not need a sign to know who is faithful. The blood was for the Israelites' benefit, not His. By placing it where only He could see it, they demonstrated that their trust was in Him alone — not in the visible display of their devotion, but in the hidden reality of it. Faith, the Mekhilta suggests, is most powerful when no one else can see it.