How does Twain express his skepticism toward men who claim to be "reformed" and those who push to "reform" others?

"I think this has much to do with Pap swearing to the judge that he will change his ways, stop drinking and become a god fearing Christian if he can take custody of Huck. Twain shows the self-righteous judge to be naive, only believing Pap to further his own belief in sin and repentance. The reformer gets more out of the deal than the person reforming; it validates the reformers powers of perception and "healing". The irony or truth is that that Pap tearfully repents and then gets drunk again."