How does A Tale of a Tub criticize religious corruption and pedantry?

In A Tale of a Tub, Jonathan Swift employs satire to critique the corruption of religion and the dangers of pedantry. Swift, an Anglican clergyman, viewed rational faith as threatened by both Roman Catholicism and Nonconformist extremism, which he characterized as irrational fanaticism.1

The work utilizes parody and allegory to trace these religious and intellectual failings to a common source: the abandonment of reason and common sense. Specifically, the "Tale" itself targets gross corruptions in learning and faith, while the "Discourse Concerning the Mechanical Operation of the Spirit" ridicules the performative, enthusiastic preaching styles of the era.21

Swift famously compared his work to a tub tossed to a whale, serving as a decoy to distract from and deflect criticism of the state and established religion. By exposing the irrationalities that disturb human faculties, he defended literature and faith against the encroaching influence of zealous pedantry.21