I don’t know if scandals can really discredit a religion, this is mostly not how cult beliefs work; they seem to gain adherents largely through manipulation and force, which are not holds that a scandal is very effective at breaking. I’d suggest the results that Madison is citing are not the results of scandals but instead of rising levels of education and living standards, which do in fact break the hold of cults (by decreasing general ignorance and increasing emotional well-being, and thereby reducing the desperation that makes people vulnerable to dependence on authoritarianism and other comforting lies in the first place).

However, he does bring up a point against Christianity that I like at the beginning. I’ve heard Christians say that clergy are less likely than laymen to go to heaven, an admission that they observe corruption in those who are supposed to be closest to God. So where is the ennobling influence of the Holy Spirit? Where is God’s discernment in picking the virtuous to represent him? The corruption of the clergy is a pretty solid bit of evidence against religion.