“We know that our old self [our human nature without the Holy Spirit] was nailed to the cross with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin. For the person who has died [with Christ] has been freed from [the power of] sin. Now if we have died with Christ, we believe that we will also live [together] with Him,”
Once something or someone has been crucified, the life of the thing or that individual has come to an end. Why? Because crucifixion is death and once you have nailed something to the cross in death you cannot bring it back to life. When you come to Christ and Christ nails your old man, the sinful nature to the cross in death, it all ends there. Your slavery to that sin is no longer relevant because the power that those sins had over you have now been buried meaning they cannot come back because death is once and for all. Dying with Christ completely frees you from the grips and the chains of sin, and resurrecting with Christ gives you a new life.
Resurrecting with Him gives you a life that is no longer bound to sin. A life that has no obligation to defile itself in the name of sin. Dying with Christ brings about your freedom, and because the dead remain dead you also must remain dead to the sin that was nailed to the cross. Only a fool goes back to his vomit and picks back up all the filth and disease stricken mess that came out only to put it back into his body. That is what it’s like to go back to your sins trying to resurrect it. It’s like going to your feces and trying to consume the poison that was flushed into the sewer.
Remain dead to sin because it is only in remaining dead to it that one can truly live and do so with Christ Jesus our Lord.