There is a line in the Catholic mass (and similar ones in most other Christian orders of service), where the worshippers ask to be forgiven "for what we have done and what we have failed to do".

Exactly. On a personal note, I have little doubt that I would have done what Vir did in that situation, or even less; and probably I would not have gone as far as he did later to make amends. He is an amiable everyman, and an entry character for a lot of people. Perhaps that's why he got the (relatively) happy ending.