My own view and definition of would be something to this effect:
Moral psychology, is the science of human ethics and morality. Why do people speak, think, perceive and behave in moral terms? What is the relationship between religion and spirituality to morality? Where do people derive their sense of right and wrong from, whether they are religious or secular or simply - uncommitted? Does it make any difference in reality, whether people believe in God or not? What is the place of the concept of God in moral psychology?
What is the importance of studying and researching about moral psychology?
What would be the difference between spiritual psychology, moral psychology and pastoral psychology?
What is the significance of defining morality as absolute or relative?
How is moral psychology be different from the psychology of religion?