Especially at Easter Jesus is referred to the Paschal (or Passover) Lamb as in "The Lamb of God who takes away the sin of the world".
Wait.
The Passover lamb is not atoning, it is providential. Atoning comes from the Yom Kippur goat.
Sin offerings in the OT are usually (always?) bulls (Lev4).
John the Baptist was referring to Isaiah chapter 53 describing the suffering servant.
Before Jesus, that servant was not understood as the Messiah. The Messiah will conquer and resolve all things to peace.
Just like the Suffering Servant was merged with the Messiah, so is the Passover Lamb merged with the Scapegoat.
Meeting notes are here
In what ways is the sacrifice of Jesus like the Passover Lamb?
In what ways is the sacrifice of Jesus like the scapegoat?
How is being given to Azazel like being given to Pilate?
"He decended into Hell" like being in the wilderness, outside God's city?
Is it significant that Jesus is crucified outside the city wall?