Throughout the Bible, Jesus is referred as the Lamb of God, especially in the Book of Revelation, but this name and symbol was derived during the most important of Jewish events, the Passover. The Passover is celebrated fourteen days into the first month (Nisan, the fifteenth day) in the Hebrew calendar, and goes for seven days while eating unleavened bread. In the mid afternoon a lamb was prepared to be eaten by the Israelite slaves in Goshen, in Egypt, after Pharaoh hardened his heart after the nine of the ten plagues that swept across Egypt (except for Goshen). Moses and Aaron warned him about the plagues but Pharaoh did not concede. The Blood of the Lamb was sprinkled on the doors, but not on the bottom of the doors to be trampled underfoot. This Lamb was a symbol that protected them from the Angel of Death that came to Egypt to kill the firstborn sons, the last of the ten plagues.
Jesus has many similarities with this Passover Lamb sacrifice and offering. The Passover Lamb was eaten, and its blood protected the families of Israel in their houses. The wages of sin is death, as the Bible states. What did the Passover Lamb protect the families from? None other than the Angel of Death. Jesus is the Lamb of God who sits at the right hand of the Father. By taking communion his Blood cleanses us from all sin, and covers our sin, so he took the wrath of God for us, being an offering and sacrifice for our sin.