"The blood will be a sign for you on the houses where you are; and when I see the blood, I will pass over you. No destructive plague will touch you when I strike Egypt." Exodus 12:13
The final plague--the death of the firstborn--was the most costly. God's power over life and death would not only demonstrate His supremacy over the Egyptian gods, but it would also bring the people who followed those gods to their knees.
But along with the plague, God offered a remedy. The death of an unblemished lamb would appease. The blood of this sacrificial lamb applied to the top and sides of the door frame would be a sign for the Lord to keep the destroyer away. The blood of the lamb saved those that applied it from death. It still does. Peter explained, "For you know that it was not with perishable things such as silver or gold that you were redeemed ... but with the precious blood of Christ, a lamb without blemish or defect" (1 Peter 1:18-19).
The penalty of sin is death, a penalty that Jesus took on Himself. "For Christ, our Passover lamb, has been sacrificed" (1 Corinthians 5:7). Because of Jesus, eternal death passes over us, and we pass over from physical death to eternal life. It is not by our baptism, confirmation, first communion or good works that we are saved. In the words of the hymn, What can wash away our sins? Nothing but the blood of Jesus!
Father, thank You for the sacrifice of Your Son, Jesus Christ. Words cannot express our gratitude. In His name we pray. Amen.