The StarkNotes-SparkNotes interpretation is as follows:
In four pages, Chekhov allows us to see Ivan's past, present and future. His dad was a churchman (Pevear and Volokhonsky's translation -- the best one -- says he was a verger), his son did not reject that, but embraced it.
He will become a good priest.
If that's all Chekhov accomplished, it would still be plenty. I now know Ivan more than I know most people I've met.
Even though he's only a naive brat in training for his life's calling, he has partly crossed the boundary line imagined by Blake, from Innocence to Experience. He is aware of what Nietzsche called the Eternal Recurrence, and early in the story the cycle is all negative, provoked at least in part by the weather that he considers out of sync, order, harmony. For ex., "when another thousand years had passed, life would be no better."
We know he is a man-child of empathy and can project -- going beyond the text -- his feelings onto St. Peter and Jesus, and in so doing he moves from gloom to "an inexpressibly sweet anticipation of happiness, . . . an unknown mysterious happiness." And I liked that he imagined Peter first denied Jesus "because he became confused."
Key words in the story's final sentence: "anticipation," "seemed," and, my favorite " -- he was only 22 --". A more vulgar writer would've added, "The poor bastard doesn't know what he's for."
That last one (the 22, not the poor bastard) actually makes my eyes water.
I set out to write two sentences, but I keep remembering more jewels. Out of all the people Chekhov could have had Ivan stop and talk with, he chose poor widows, one of them probably with special needs. And just the enthusiasm, the spirit in which he recounted the story moved his "congregation" to tears without a didactic breath.
You would've had to give him an "A" in your Zoom class!