As Christians we daily battle with our sinful nature as we try to deny the desires of the flesh in favor of walking in the Spirit. Paul reflected on this battle in Romans
For we know that the law is spiritual, but I am of the flesh, sold under sin. I do not understand my own actions. For I do not do what I want, but I do the very thing I hate. Now if I do what I do not want, I agree with the law, that it is good. So now it is no longer I who do it, but sin that dwells within me. For I know that nothing good dwells in me, that is, in my flesh. For I have the desire to do what is right, but not the ability to carry it out. For I do not do the good I want, but the evil I do not want is what I keep on doing. Now if I do what I do not want, it is no longer I who do it, but sin that dwells within me. So I find it to be a law that when I want to do right, evil lies close at hand. For I delight in the law of God, in my inner being, but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members. Wretched man that I am! Who will deliver me from this body of death? Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin. Romans 7:14-25Peter as Spiderman desired to do what is good, largely out of a sense of penance (how Papist of him) but when he came in contact with the black suit he changed. While he desired to do good, he ended up doing that which is bad. Just to make things even better sin aka the black suit bound his desires to itself. He wanted to hurt people right up to the point he was faced with his sins when he struck Mary Jane. At which point he desires to cast off the black suit, but he cannot because he is so bound by the suit.
Just to make things better from a Lutheran point of view, the black suit cannot be cast off until outside intervention breaks the hold of the suit and chases it off of Peter. In the movie it is the ringing of a bell that drives the black suit off of Peter. This draws the parallel that we cannot cast off sin ourselves but the vicarious act of atonement which happens outside of us releases us from the bondage of sin.
I realize the illustration isn't perfect but it does make for an interesting way to describe an ancient truth.