] ..upon his departure on Saturday he said: “I must go away directly, two days before I intended it.”
] So initially he did not intend to perform his duties that Sunday.

Good point.

Incidentally, how good a clergyman do you think Henry is? He doesn't seem very assiduous in his duties, handing them to his curate and taking most of the income. It's not as though he's incapacitated or too old to perform the duties, but he prefers to go to Bath or to stay at Northanger Abbey.

I guess that when he does perform them, he gives sound and well-informed advice, based on good principles and charity -- and I bet he delivers a good sermon when he can contrive to stop showing off how clever he is.