This is one of those times when Twain exposed his true nature and quest, in my opinion:
And as for me, all that I think about in this plodding sad pilgrimage, this pathetic drift between the eternities, is to look out and humbly live a pure and high and blameless life, and save that one microscopic atom in me that is truly me :  the rest may land in Sheol and welcome for all I care.
My view of it is that Twain was just about as true to himself and his ideals as it is possible for a human to be. Yet he was not self-righteous; if anything, the opposite - playing down, hiding, and trying to cover up just how good a man he was.

- B. Clay Shannon