The Institutes, Book 11
Attacked on the Right Hand and on the Left
So whoever wants to travel the King’s highway with “the weapons of righteousness on the right hand and on the left” ought, as the apostle teaches, to pass through “honor and dishonor, bad report and good report.” With such care he must steer his virtuous course through the swelling waves of temptation, with discernment at the helm and the Spirit of the Lord breathing on us. For we know that if we swerve even a little to the right hand or to the left, we will soon be dashed against the most dangerous crags. That is why Solomon, the wisest of men, warns us: “Do not turn aside to the right hand or to the left.” That is: do not flatter yourself on your virtues and be puffed up by your spiritual achievements on the right hand; and do not swerve on the left hand into the path of vices and seek from them, to use the apostle’s words, “glory in your shame.”
Where the devil cannot breed empty glory in a man through neat, well-fitting clothes, he tries to bring it in through a dirty, cheap and neglected style. If he cannot drag a man down by honor, he overthrows him by humility. If he cannot puff him up by the gift of knowledge and eloquence, he pulls him down by the weight of silence. If a man fasts openly, he is attacked by the pride of vanity. If he hides his fasting so as to despise the glory of it, he is assailed by the same sin of pride. So as not to be stained by empty glory, he avoids making long prayers in sight of the brothers; and yet, because he offers them in secret where no one knows of it, he does not escape the pride of vanity.