The vicarious humanity of Jesus
This stunning truth tells us that our salvation is not merely something that Jesus did for us, but who Jesus is for us, as one of us (the Incarnation continues!). Our salvation is thus far more than a legal (forensic) transaction that was accomplished by Jesus's death to pay for our sin. His death did accomplish that necessary payment (praise God!), however, it is the total scope of Jesus' continuing vicarious humanity that accomplishes and secures our salvation.
Our salvation truly is "in Christ" - the incarnate, crucified, risen and ascended God-man, who has included us in God's love and life; a love and life that we personally experience as we trust in Jesus.
Here is part of what Torrance writes:
God, in taking to himself in Jesus our flesh and blood, became not simply a man but Representative Man. He related himself to us all. That is, in Jesus, God once and forever, for all eternity, joined himself in the flesh to the whole of humankind. Men and women, for better or for worse, are united with God in an eternal covenant of Grace through the Holy Spirit, which they cannot break. This means that all that happened to Christ affects our life and being. Christ and all humanity are wrapped together in the same bundle of life for eternity.
Because God became Man, once and forever, in Christ Jesus, God has put his seal on our humanity. The incarnation guarantees our humanity and the safety of all creation. Because of sin, the world was hurtling to destruction. Humankind was destined for death and destruction. God intervened. He entered into this world. He took hold of it making a covenant of Grace and life first through Noah and then through Abraham and his seed, Israel. That covenant of grace and life he fulfilled, confirmed and forever sealed in Jesus Christ who is the Creator Word made flesh, our flesh. God conquered the powers of death and destruction by becoming Man in Jesus Christ (p. 5).