Blessed is the man who knows his own weakness, because this knowledge becomes to him the foundation, root, and beginning of all goodness. For whenever a man learns and truly perceives his own weakness, at that moment he contracts his soul on every side from the laxity that dims knowledge, and he treasures up watchfulness in himself. But no one can perceive his own infirmity if he is not allowed to be tempted a little, either by things that oppress his body, or his soul. For then, comparing his own weakness with God’s help, he will straightway understand the greatness of the latter.
St. Isaac the Syrian
“Ascetical Homilies” (Homily 8)