"...On the fourteenth day of the first month at twilight is the Lord's Passover" (Leviticus 23:5)
When God delivered Israel from the bondage of slavery, he brought 10 plagues upon Egypt. The last plague was the death of the firstborn throughout the land. The only ones to survive this plague of death were those who placed the blood of a spotless lamb upon the doorposts of their dwelling. For those covered by the blood, death "passed over" and they lived.
Today Passover is a commemoration; a remembrance of this deliverance and of the message - Salvation is by the blood of the Lamb! Throughout the world millions celebrate Passover each year with a special meal called a "Seder". "Seder" means "Order", a Seder meal is an ordered recounting of the story of God's deliverance - Past, Present and Future - by the Blood of the Lamb.
From Egypt to the present day, the Feast of Passover declares the Salvation of God for all His people - Salvation through the Blood of the sinless Lamb of God - Yeshua, Jesus Christ!