With the single exception of sin, anxiety is the greatest evil that can happen to a soul. Just as sedition and internal disorders bring total ruin on a state and leave it helpless to resist a foreign invader, so also if our heart is inwardly troubled and disturbed it loses both the strength necessary to maintain the virtues if had acquired and the means to resist the temptations of the enemy. He then uses his utmost efforts to fish in troubled waters, as they say.

St. Francis de Sales

Salesian Spirituality