Paul talks about the death of Christ as if he (Paul) participated in it. With this language he emphasizes two realities. First, he emphasizes the death of the old self (Ephesians 4:22; Colossians 3:9).1 No longer does Paul live for Paul; he now lives for Christ. Second, he refers to his union with Christ. Through faith, the believer is united to Christ in such a way that the death of Christ is considered to be the death of the believer.2 That is to say, when Christ died, he paid the penalty for the sins of all those who trust in him. Believers will not have to pay that penalty for themselves because it has already been paid in Jesus’ death. Essentially, in Christ, the believer has died the death that his sins deserve.
20 I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.