Blood has been thought of as the source of life in the Bible. Why blood in the Passover? The Old Testament covenant was established by the death of animals. In Genesis 15 God made a covenant with Abraham.
Genesis 15: 9 The Lord told him, “Bring me a three-year-old heifer, a three-year-old female goat, a three-year-old ram, a turtledove, and a young pigeon.” 10 So Abram presented all these to him and killed them. Then he cut each animal down the middle and laid the halves side by side;… 13 Then the Lord said to Abram, “You can be sure that your descendants will be strangers in a foreign land, where they will be oppressed as slaves for 400 years. 14 But I will punish the nation that enslaves them, and in the end they will come away with great wealth…17 After the sun went down and darkness fell, Abram saw a smoking firepot and a flaming torch pass between the halves of the carcasses. 18 So the Lord made a covenant with Abram that day.[1]
Blood in the 10th Plague
An innocent lamb died as a substitute sacrifice in the place of the first born of the house. The lamb’s blood had been painted on the door posts. This way the death angel would pass over the house. In the first Passover the blood on the doorpost served as a visible symbol of the faith of the residents of the home. This meant they had accepted God’s plan for their rescue and had put their trust in God.
This smearing of blood was a one-time ritual. Every year after this, the blood of the lamb was sprinkled on the altar first in the Tabernacle and later in the Temple. Thus, the blood was shed for purification and redemption.
Jesus’ Blood Shed for Us
While the Old Testament covenant was established by the death of animals, the new covenant was established by the death of Christ.
Hebrews 9: 13 Under the old system, the blood of goats and bulls and the ashes of a heifer could cleanse people’s bodies from ceremonial impurity. 14 Just think how much more the blood of Christ will purify our consciences from sinful deeds so that we can worship the living God. For by the power of the eternal Spirit, Christ offered himself to God as a perfect sacrifice for our sins. 15 That is why he is the one who mediates a new covenant between God and people, so that all who are called can receive the eternal inheritance God has promised them. For Christ died to set them free from the penalty of the sins they had committed under that first covenant.[2]
Both covenants required the shedding of blood for purification and redemption. All through Scripture blood is key to bring atonement or making of amends for human sin. The sacrifice of animals was only a temporary solution until Christ, the perfect lamb made His sacrifice on the cross. This is the reason that we can be forgiven of our sin.
Why blood in the Passover? Find more here:
https://podpoint.com/light-of-christ-church-podcast/foreshadowing-of-the-cross-passover
[1,2]Holy Bible, New Living Translation, copyright © 1996, 2004, 2015 by Tyndale House Foundation Tyndale House Publishers, Inc., Carol Stream, Illinois 60188.