The letter of the Law can be quite deadly

I have observed a peculiar kind of logic in certain pious people. Their piety is a good thing, and their predisposition for good is also a good thing; however, a certain spiritual discernment and amplitude is required so that their piety is not accompanied by narrow-mindedness or strong-headedness. Someone who is truly in a spiritual state must possess and exemplify spiritual discernment; otherwise he will forever remain attached to the “letter of the Law”, and the letter of the Law can be quite deadly.

“Saint Paisios the Athonite”