The Jews expected the Messiah to be born in Nisan, the first month of the year in the Jewish calendar. He was indeed born at this time. This month marks the season of the Exodus from Egypt and the Passover celebration of it.
Lamb of God is the title given to Jesus by John the Baptist.
John the Baptist’s mother was Elizabeth, a relative of Mary who was a generation older than her. Elizabeth was probably Mary’s mother’s sister and so Mary’s aunt. This means that Jesus and John the Baptist were first cousins once removed.
In the gospel of the Apostle John, John the Baptist twice says “Look, the Lamb of God” as Jesus came near (John 1:29; 1:36). This is strange phraseology, unless John the Baptist, being his cousin, knew that Jesus was born at Passover. This point is noted by Colin Humphreys. I believe that Jesus’ circumcision eight days after birth corresponded to the day that the sacrificial Passover lambs were chosen.
“The next day John was there again with two of his disciples. When he saw Jesus passing by, he said, ‘Look the Lamb of God!’ When the two disciples heard him say this, they followed Jesus.” (John 1:35-37)
The two disciples of John the Baptist were Andrew and John the Apostle himself. They both become disciples of Jesus. Andrew brings his brother Simon who becomes the Apostle Peter.
‘The Lamb’ is a title used by the Apostle John in the book of Revelation. It is The Lamb who opens the seven seals of the scroll that reveals the destiny of the world.
When John the Baptist called Jesus the ‘Lamb of God’, he did not know that Jesus would die at Passover. John the Baptist died before his time at the hands of Herod Antipas (also known as Herod the Tetrarch, son of Herod the Great) in 28-29 AD. This was before Jesus died in 33 AD.
Therefore, the title Lamb of God comes from Jesus’ birth at Passover in 5 BC, but the mission of Jesus was accomplished in his death at Passover in 33 AD. Colin Humphreys and I believe this. In addition to this I believe that Jesus received the mark of being chosen on the day that the Passover lambs were being prepared.
It means that both Jesus’ birth and death were linked to his identity of being the Messiah who would appear in Nisan, the first month of the year.