Why the Blood?

Why did Christ shed His blood when dying for us? Did His literal, physical blood have atoning value? Can literal, physical molecules of blood procure a salvation that is spiritual in nature? Are the Biblical references to the shed blood of Christ merely figurative in nature, pointing perhaps to the idea of a violent death, or perhaps - by metonymy - to the concept of death itself? Is it Christ's death itself that saves, or the shed blood of Christ, or perhaps both in combination? These are questions this message addresses so that believers might understand the salvation that God has provided for us and why we memorialize the blood of the Lord every time we observe the Lord's Supper.