The Israelites at the time of the exodus knew they had escaped the night of God’s judgement through trusting in the blood of the Passover lambs on their doorposts.Terry Virgo, God's Lavish Grace, (Oxford, UK: Monarch Books, 2003), 45
Notice that the blood was to be placed on the outside of their houses. The blood was for God to see, not for their benefit. The blood was not to make them feel good or feel safe. The blood was not for their feelings at all. The blood was to satisfy God. It was for his eyes alone. God said, ‘When I see the blood I will pass over you’ (Exodus 12:13).
We have peace, not because we feel good, but because God is satisfied with the blood. Only he can evaluate the worth of the lamb. Because he is satisfied, we have peace.
Borrowed shamelessly from OFI