Romans 6:5-7 meaning

Paul is doubling down on his rebuttal to the slanderous charges of the competing Jewish "authorities" in Rome. They have accused him of teaching that sinning honors God (Romans 3:8), and he is refuting the accusation. It is likely that this letter to the Roman believers is, in part, intended to support Aquila and Priscilla, who were fellow Jews who preached the gospel with Paul in Greece, and are now returned to Rome where they have started a church in their home (Romans 16:3-5, Acts 18:2, 18, 26).

Paul reminds the Roman Christians of the foundation of our faith: the death and resurrection of Jesus Christ, and that those who believe in the gospel have been spiritually baptized (immersed, identified) with Jesus: For if we have become united with Him in the likeness of His death, certainly we shall also be in the likeness of His resurrection (v 5).

Paul reasons that if we Christians were united with Jesus in the likeness of His death (dying to sin), it is certain that we share the likeness of His resurrection and new life. Knowing this, that our old self that wishes only to please itself was crucified (put to death) with Him when He died on the cross, in order that our body of sin might be done away with, so that we would no longer be slaves to sin (v 6). Paul highlights that the reason our old self dies is to free us. Jesus Christ did this so we might no longer be enslaved to our sinful natures: For he who has died is freed from sin (v 7). We share in Christ's death so that we can choose to live in a way that pleases God.