There are people in the church who believe that through his suffering on the cross the Lord took away our sins and made satisfaction to the Father, and by so doing brought about redemption. Some also believe that he transferred to himself the sins of those who have faith in him, carried those sins, and cast them into the depths of the sea—that is, into hell. They support this among themselves by what John says of Jesus,
Behold the Lamb of God, who is taking up the sins of the world. (John 1:29)
and by the Lord’s words in Isaiah,
He bore our diseases and carried our sorrows. He was pierced because of our transgressions and bruised because of our iniquities. Chastisement was upon him for the sake of our peace; with his wound, healing was given to us. Jehovah made the iniquities of us all fall upon him. He was oppressed and afflicted, but did not open his mouth, like a lamb being led to slaughter. He was cut off from the land of the living. He suffered a blow because of the transgression of my people, to send the ungodly to their grave and the rich to their deaths. As a result of the labor of his soul, he will see and be satisfied. By means of his knowledge he will justify many, because he himself carried their iniquities. He emptied out his own soul even to death and was counted among transgressors. He bore the sins of many and interceded for transgressors. (Isaiah 53:3–end)
Both of these passages are talking about the Lord’s trials and suffering; his taking up our sins, [bearing] our diseases, and having the iniquities of us all fall upon him mean something similar to his carrying our sorrows and our iniquities.
So I need to say first of all what his carrying iniquities means and then what his taking them up means. The true meaning of his carrying iniquities is that he was subjected to severe trials and endured being treated by the Jews the way the Word was treated by them; and they dealt with him in that way precisely because he was the Word. The church among the Jews was in utter shambles at that time; it had been brought to ruin by their perversion of everything in the Word to the point that there was nothing true left. As a result, they did not recognize the Lord. That is in fact the intent and meaning behind each detail of the Lord’s suffering.
from The Lord, Section 15