In 1 Peter 2:18-25, Jesus is presented as both our Example and our Substitute. In His suffering, Jesus left us an example to follow when we suffer (2:21). And in the suffering of the cross He provided forgiveness of sins and eternal life for all who believe in Him (2:24).
In specifically addressing Christian slaves or servants, the apostle Peter indicated that some of them were suffering unjustly. While it is wrong for a person to enslave another person, and treat him as property, there were some slave owners in Peter’s day who were good and gentle, and some who were unjust. The apostle exhorted those who were being treated unjustly to follow the example of Christ. They were being beaten for faults they had not committed, and Jesus died for sins He had not committed. Jesus provided an example as to how we ought to respond when we suffer unjustly.
Jesus’ suffering on the cross was different than that of the Christian slaves. They suffered for things they had not done; Jesus suffered for things we had done. So Jesus is our Example in suffering, but also our Substitute. When He suffered and died it was not for His sins (He was without sin), but for our sins. He died in our place that we might be saved from our sins. Jesus saved us from the penalty of sin in that He paid it. He also saved us from the power of sin in that we might die to sin and live for righteousness.