Some laws can straddle the religious/secular divide pretty comfortable. Stealing? We're pretty sure God wouldn't want you to do that. Murder? Definitely not. But what about driving without your license? Or doing some underage drinking (which Shmoop firmly disapproves of)? Does God care about those laws? If you lived in Puritan America as represented by The Scarlet Letter, the answer would be yes: there's no difference between God's law and man's law. Breaking colonial law is the same as breaking God's law. On the one hand, great: at least there's clarity, right? On the other hand, the conflation of God's law with man's law creates an intolerant, authoritarian society with no room for human mistakes. Not too cool.
The townspeople in The Scarlet Letter want justice, even if they have to overlook the truth.
The most painful kind of judgment inflicted in this novel is self-judgment.