The overall principal of reading literature like a professor, as stated by Thomas C. Foster, is that the reader must know the rules and conventions of literature. As he states, there are "types of characters, plot rhythms, chapter structures, point-of-view limitations" among other rules and conventions, like archetype characters and situations.
Applying this briefly to Irving's A Prayer for Own Meany, one convention is that when the first-person narrator has a heavily ironic voice, the reader may expect to read farce or satire. When the subject matter is dark, then the reader might expect to read a moral life lesson that proceeds out of dubious events. A Prayer opens with both these conventions and proceeds to tell the story of how Owen Meany was treated and the effect that had upon the narrator's life.
I am doomed to remember a boy with a wrecked voice ... I have a church-rummage faith--the kind that needs patching up every weekend. What faith I have I owe to Owen Meany ... In Sunday school, we developed a form of entertainment based on abusing Owen Meany ....