Thus far in this paragraph Peter had been using the second person plural pronoun “you.” Now he shifts to the first-person plural (and reverts back to the second-person plural at the end of this verse). We could attribute the change simply to the fact that Isaiah used the first-person plural pronoun “our” in the verse Peter is quoting (Isaiah 53:4). But Peter is also expressing solidarity with his readers on the basis of his own sins at Jesus’ arrest and trial, and so confessing that Jesus’ suffering atoned also for his own sins.
24 He himself bore our sins in his body on the tree, that we might die to sin and live to righteousness. By his wounds you have been healed.