Caesarius of Arles : Original sin could not have easily been forgiven, if a victim had not been offered for it, if that sacred blood of propitiation had not been shed. Even then the words in Exodus were not vainly said of our Lord: "I shall see the blood and shall protect you." That figure of the lamb represented this passion of Christ our Lord. Blood is given for blood, death for death, a victim for sin, and thus the devil lost what he held. — SERMON 11.5