John 10:38
38 but if I do them, though you do not believe Me, believe the works, so that you may know and understand that the Father is in Me, and I in the Father.”
Good theology is necessary for good psychology, or in other words what you believe will affect how you behave! Your belief system is the engine that drives you. What you believe now is indicative of future actions. Someone who believes they want to be a doctor today will take the necessary science course to fulfill that belief. If we believe in eternity our behavior should be indicative of that. How you behave should align with what we believe. When my steering wheel in my car is out of alignment with my wheels I will go and get my wheels aligned. If behavior is out of alignment with what we believe, we can ask the Lord to align our behavior with what we believe.