tone
That is the story's tone.
moralizing according to religion
moralizing example exemplum
A moralizing example or a prop for an intellectual idea is referred to as an exemplum.
Moralizing literature, or literature that has moral lessons have been popular since the beginning of time. Moralizing literature can be written for adults or children and include books such as the Bible, and Goldilocks and the Three Bears.
Moralizing
A tedious moralizing lecture or admonition.
moralizing story
yep
exemplum ..amber apex..
William Hogarth
"Sententious" describes someone who tends to speak or write in a self-righteous or moralizing way, often expressing opinions in a pompous or excessive manner.