I am (YHVH Elohim) . . . your Savior, I gave Egypt for your ransom . . . I give men for thee and people for thy life (Isaiah 43:3 - 4).
The blood over the doorposts kept the firstborn of Israel from becoming part of the ransom. A ransom is a price paid to set the captured free. It should be obvious that the lambs Israel killed for the Passover were not the ransom. Pharaoh could have said, "So you killed some lambs! Now get back to making bricks!"
Christ the Ransom
The Son of Man came . . . to give his life a ransom for many (Matthew 20:28, Mark 10:45, 1Timothy 2:6, Isaiah 35:10).
Christ our Passover was sacrificed for us (1Corinthians 5:7). He was not passed over on that 14th of Nisan. The church of God partakes of the token wine as firstfruits so that we will be passed over and not be dead during the millennium reign. But Christ’s life is the Ransom for the whole world for freedom from enslavement of sin.
Burned not buried
Christ was buried at the end of the 14th of Nisan. Notice the bodily remains of the lambs in Egypt were burned, not buried as a type of Christ’s burial. The blood the night before was a token. What was buried in Egypt as the Israelites were leaving? The Ransom, the Egyptian dead (Numbers 33:4).
As the end of the 14th (sundown) was turning to the "morrow," beginning of the 15th, the hundred thousands of Israelites began journeying out of Egypt. The miles-long assembly were journeying out all night the 15th (Deuteronomy 16:1). What was buried at the end of the 14th at Jesus death? It was the Ransom, Firstborn of God.
The firstborn of Egypt was a major type of Christ. The tokens in Egypt were the blood of the lambs and the unleavened bread. The firstborn of Egypt was the ransom. The tokens for the church are the wine (blood of the grape) and the unleavened bread. The Ransom is Christ, the Firstborn of God.
When Was the Ransom Taken?
The firstborn of Egypt was Israel’s ransom (the type) after midnight on the 14th. The Passover had already been eaten. Christ’s crucifixion was the ransom antitype on the 14th after midnight. The Passover had already been eaten with His disciples.
Many of the Jews were killing lambs at the temple as Christ was dying. What they were killing was really the Holy Day sacrifice (for the night to be observed, Leviticus 23:8). In confusion, they were calling it the Passover, "the feast of unleavened bread CALLED the Passover" (Luke 22:1) or "The Jews’ Passover" (John 11:55). But Jesus kept "THE Passover" (Luke 22:7, 11, 15), the "Lord’s Passover" (Leviticus 23:5), not the Jews’ Passover.
In Numbers 9:1 - 15 and Exodus 12:6 we find all the rites and ceremonies were to be on the 14th. Leviticus 23:32 makes clear that any day is from even to even (Leviticus 22:6, 7). The eating was part of the rites. It had to be eaten on the 14th between the sunsets and at night (Exodus 12:8). The burning of the bones was part of the rites. They had to be burned on the 14th between the evenings (sunsets), so they could be burned the next morning (day portion of the 14th, see Exodus 12:10).