An important consequence of giving highest priority to the metaphor of Moral Strength is that it rules out any explanations in terms of social forces or social class. If it is always possible to muster the discipline to just say no to drugs or sex and to support yourself in this land of opportunity, then failure to do so is laziness and social class and social forces cannot explain your poverty or your drug habit or your illegitimate children. And if you lack such disciple, then by the metaphor of Moral Strength, you are immoral and deserve any punishment you get.
Sorting out the Christian essay topics is a laborious and time consuming process, as you have to become familiar with specific terms and historic events described in the Bible in order to understand what you are writing about. Try to select one of the Christian essay topics that you are familiar with to some extent, so you can handle it. Choose a topic that has kind of a hook and not only relates to Christianity, but also is of interest to you, as working with something that is interesting gives better results and makes the process of working more enjoyable.