There was double imputation at the Cross of Jesus Christ! And we can only stand and watch at a Distance, while it was being executed by God the Father!2 Corinthians 5:21:

There was double imputation at the Cross of Jesus Christ! And we can only stand and watch at a Distance, while it was being executed by God the Father!
2 Corinthians 5:21:
21He made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him!

As the Nails were Driven in Jesus Hands and Feet, and the Crown of thorns around His head; So was the Wrath of God inflicting the eternal pain and penalty of our sins on Jesus Christ.
As the Spear pierced Jesus' side, with that firm thrust in, to break open the Righteousness of Jesus Christ, and the spear being pulled out as blood and water flowed from Jesus' heart; so that we may receive cleansing in His blood and His righteousness imputed by God the Father to our account, of those who believe on the Lord Jesus Christ for Salvation!

Something we did not do, but that God in His Mercy and Grace did on our account, in that while we were yet sinners, Christ Died for the ungodly; we would not care to do it, indeed in our righteousness we would seek to make atonement for our own sin, to appease our own conscience, not to appease the wrath of God! God had to do it and drive the nails of our sin into Jesus Christ--Jesus gave of himself, and the Father pierced through His Wrath on His Son, we just stood by watching like the roman soldiers, the Imputation of our sin was put on the Son by God and He who knew no sin became sin for us; and the double imputation, was that as the spear pierced Jesus' Side and was thrust into Jesus' side, while coming out of Jesus' Side flowed blood and water for the imputation of our cleansing and Imputation of Jesus righteousness credited to our account!

"We took our sins and drove them like nails through his hands and feet. We lifted him high up on the cross of our transgressions, and then we pierced his heart through with the spear of our unbelief."C.H. Spurgeon

Double Imputation is a doctrine related to Justification, which views the concept of Imputation as applying both to Christ and believers; On the one hand, our sins are imputed to Christ who bore them on the cross. On the other hand, Christ's righteousness is imputed to believers whereby they are seen by God as cloaked in the righteousness of Christ. Justification, in this view, is based on Christ's propitiatory sacrifice as well as his personal righteousness imputed to believers, not any righteousness inherent or infused in man.Nails Driven in by the Hand of God’s wrath, that He who knew no sin became sin for us that we might become the righteousness of God

The Spear Piercing His Side with the thrust of the spear in His Side and out of His Side flowed the Blood and water for our Cleansing in His blood and for God to impute His righteousness to our account!

Matthew 27:54-55
54Now the centurion, and those who were with him keeping guard over Jesus, when they saw the earthquake and the things that were happening, became very frightened and said, "Truly this was the Son of God!" 55Many women were there looking on from a distance, who had followed Jesus from Galilee while ministering to Him.…

John 19:34-35
33but coming to Jesus, when they saw that He was already dead, they did not break His legs. 34But one of the soldiers pierced His side with a spear, and immediately blood and water came out. 35And he who has seen has testified, and his testimony is true; and he knows that he is telling the truth, so that you also may believe.…
I would have to go further than where this quote was left by Charles Spurgeon: