Christianity and psychology are about a whole lot more than inappropriate behavior. Sure, some people like focusing just on those things. In some ways, such a concrete focus is easier because it can clearly let us know if what we're doing is working or not.
But just as I did not go into the field of psychology to reduce symptoms, I did not accept a relationship with Christ to reduce sin. I pursued both to become transformed and help other become transformed.
In order to become transformed, we do usually need to change some of our behavior. But that is simply a means to an end. We need to address aspects of our lives that impede transformation. Yet we need to keep our eyes on the ultimate goal of being like Christ, not just in behavior, but in mind, body, and spirit.
We also need to remember Paul's words in Romans 8:12-17 that we are no longer slaves to sin nor under any obligation to sin. Yet we frequently believe the lie that we are defined by sin. As John Eldredge so eloquently states in Wild at Heart:
You are not your sin; sin is no longer the truest thing about the man who has come into union with Jesus. Your heart is good. "I will give you a new heart and put a new spirit in you" (Ezek. 36:26). The Big Lie in the church today is that you are nothing more than "a sinner saved by grace." You are a lot more than that. You are a new creation in Christ. The New Testament calls you a saint, a holy one, a son of God. In the core of your being you are a good man. Yes, there is a war within us, but it is a civil war. The battle is not between us and God; no, there is a traitor within us who wars against our true heart fighting alongside the Spirit of God in us:
A new power is in operation. The Spirit of life in Christ, like a strong wind, has magnificently cleared the air, freeing you from a fated lifetime of brutal tyranny at the hands of sin and death . . . Anyone, of course, who has not welcomed this invisible but clearly present God, the Spirit of Christ, won't know what we're talking about. But for you who welcome him, in whom he dwells . . . if the alive-and-present God who raised Jesus from the dead moves into your life, he'll do the same thing in you that he did in Jesus . . . When God lives and breathes in you (and he does, as surely as he did in Jesus), you are delivered from that dead life. (Rom. 8:2, 9-11 The Message)
The real you is on the side of God against the false self. Knowing this makes all the difference in the world. The man who wants to live valiantly will lose heart quickly if he believes that his heart is nothing but sin. Why fight? (p. 144-145)
We often believe a lie that Jesus has not redeemed us, our hearts, our minds, and our behavior. We fight with ourselves to change something and then also believe we have no hope of changing it because we are irreversibly evil.
Without God, little will change. With God, everything will change. However, that does not mean our circumstances, moods, and even all behavior will change. What I have found is that often God leaves those things to help further develop our spirit and character.
Character doesn't mean perfection. It's how we respond to life, even when those responses aren't perfect.
We should continually strive to put on the character of Christ, as Dallas Willard puts it. We should also strive to refine our behavior, attitudes, and moods. Our spiritual disciplines can help with this. So can psychotherapy. Yet if all we focus on is reducing or removing a certain misdeed, we miss the bigger picture of true transformation. And that might be the biggest sin and tragedy of all.