Season three of Cobra Kai opens with the anti-hero Johnny Lawrence (the bad guy of the original Karate Kid movie) trapped in a spiritual crisis in the aftermath of season two. His son, Robby, knocks his favorite student, Miguel, over a stairwell, putting him in a coma. Miguel eventually wakes up but is paralyzed. In episode three, Johnny goes to see Bobby, one of his old pals from his Cobra Kai days, who has become a Christian minister. In a wonderful scene, Johnny pours out his heart talking about how has tried to do right and it has all gone wrong. Bobby responds: “You don’t do the right thing because it always works out. You do the right thing because it’s right.”
This scene is perfect for Johnny because our empathy with him relies on the fact that we never think of him as a good guy but as a villain who is honestly trying to be better. As such Johnny, much like Eleanor Shellstrop, gets to ask the question of why be good as something more than an academic exercise. Since our standards for Johnny are low so we judge him on a curve. This is in contrast to Daniel (the hero of the original movie), who, despite probably being a better person, still has real flaws. In essence, we judge Daniel for not being Mr. Miyagi as opposed to Johnny who just needs to not be John Kreese.
If Bobby were Jewish, his answer would make sense. Perhaps Rabbi Bobby could explain the Talmudic rule that a person who intends to do a good deed but fails, it still counts as if he did it. Johnny's job in life was never to succeed. He thought his mission was to teach Miguel karate. God runs the world and he has a plan; it just happens to be that his plan might not be ours. It very well might be that God wants Johnny to support Miguel as he learns to use a wheelchair and to let Robbie know that he is loved even if he is in jail.
From a Christian perspective and particularly from a Protestant perspective (note that Bobby makes the point several times that he is not a priest), Bobby's response is problematic. If Johnny were to seek spiritual counsel from Martin Luther, we might imagine Luther first sharing a few beers with Johnny before going after the basic flaw in his reasoning. Johnny was trying to improve the world through works. The logic being that if he taught Miguel karate, he would turn Miguel's life around and Johnny, in turn, would be transformed into a good person and find forgiveness for all the terrible things he has done, particularly for being a lousy father to Robbie.
Teaching Miguel karate was never going to change the fact that Miguel was a poor teenage kid without a father. While mastering karate might help Miguel with bullies, it would be more likely to turn him into a bully than actually make him a better person. Furthermore, nothing that Johnny can do would ever change the fact that he, Johnny, is likely to fall back on his anger and drinking when faced with difficulties.
The world runs by the rules of the Devil, manifested, in this case, in the person of Kreese. There is no defeating Kreese in this world. The only way to physically defeat him is to become like him. No matter who wins the battle, Kreese, and everything he represents, will win the war. The only way to win a fight that has been rigged against you is to recognize that the fight is rigged and refuse to play along.
What Johnny needs to do is recognize that he is a sinner, whose works, even when well-intentioned, would likely fail and cause more harm than good. As a sinner, fashioned by the same hatred for God and love for this world as Kreese, he can never defeat Kreese. The only solution for Johnny is to recognize that there was only one person in all of human history capable of being virtuous and he died on the Cross for sinners like Johnny. If only Johnny could accept him as his savior, meaning letting go of any claim to accomplish good works on his own, then he might have a chance of helping both Miguel and Robbie.
In truth, it was fine that Bobby did not mention Jesus. Still, at the very least, he should have said something to challenge Johnny's faith in works. How can he be a Protestant minister otherwise? I guess, maybe Bobby is supposed to be a Methodist but even Methodists are supposed to avoid the belief in salvation simply through works.
One of Christianity's strongest points is its theodicy. Bad things happen in this world but God does not stand aloof from it all. On the contrary, he suffered worse agonies than you can possibly imagine on the Cross and he did it because he loved even the worst "Jerusalem Sinner" (to use John Bunyan's term). Particularly relevant for someone like Johnny is Christianity's ability to handle theodicy when it becomes intertwined with personal guilt; why did God allow me to make the mistakes I have made when I honestly tried to do good? The answer is that Johnny is a sinner and such a sinner that only God could ever truly love him. And that is ok because God does love Johnny and has already forgiven him for all of his sins. In fact, God loves Johnny so much that he died on the Cross for him so that Johnny could be forgiven. If God could forgive Johnny for everything he has done, perhaps Johnny could learn to forgive himself.