What does 'the Lord hath laid on Him the iniquity of us all' mean?

The phrase 'the Lord hath laid on Him the iniquity of us all' from Isaiah 53:6 encapsulates the doctrine of substitutionary atonement. God laid the sins of His elect upon Jesus, who bore the full weight of their iniquity during His crucifixion. This act was essential for providing forgiveness and enables believers to be accounted as righteous. The sovereign plan of God required that the innocent Christ take the place of the guilty so that justice is satisfied, and mercy is extended to those He saves.