58. In drawing water from a well we sometimes without noticing it bring up a frog with the water, and so in acquiring the virtues we often get involved in the vices that are imperceptibly entwined with them.
The kind of thing I mean is that gluttony is entangled with hospitality; lust with love; cunning with discernment; malice with thoughtfulness; duplicity, procrastination, laziness, contradiction, wilfulness and disobedience with meekness; contempt of instruction with silence; conceit with joy; indolence with hope; harsh judgment with love again; despondency and sloth with quietness; acerbity with chastity; familiarity with humility; and behind them all 1as a general salve, or rather poison, follows vainglory.
St. John Climacus, The Ladder of Divine Ascent, Step 26 On discernment of thoughts, passions and virtues