Taking Yourself Too Seriously – Thomas Merton

As soon as you begin to take yourself seriously and imagine that your virtues are important because they are yours, you become the prisoner of your own vanity and even your best works will blind and deceive you. Then, in order to defend yourself, you will begin to see sins and faults everywhere in the actions of [others]. And the more unreasonable importance you attach to yourself and to your own works, the more you will tend to build up your own idea of yourself by condemning other people. — New Seeds of Contemplation (pp. 59-60, Kindle Edition)