And why do you look at the speck that is in your brothers eye, but do not notice the log that is in your own eye? Matthew 7:3 – Bible

Every man alone is sincere. At the entrance of a second person, hypocrisy begins. We parry and fend the approach of our fellow-man by compliments, by gossip, by amusements, by affairs. We cover up our thought from him under a hundred folds. – Ralph Waldo Emerson, “Friendship,” Essays, 1841

Hypocrisy is the homage that vice pays to virtue. – François VI de la Rochefoucault (1613–1680)

Hypocrisy is the most difficult and nerve-racking vice that any man can pursue; it needs an unceasing vigilance and a rare detachment of spirit. It cannot, like adultery or gluttony, be practiced at spare moments; it is a whole-time job. – W. Somerset Maugham