In time of trial it is of great profit to us patiently to endure for God’s sake, for the Lord says: “By patient endurance you will win life for yourselves.”
He did not say by your fasting, or your solitude and silence, or your singing of psalms, although all of these are helpful in saving your soul.
But he said: “By patient endurance” in every trial that overtakes you, and in every affliction, whether this be insolent and contemptuous treatment, or any kind of disgrace, either small or great; whether it be bodily weakness, or the belligerent attacks of Satan, or any trial whatsoever caused either by other people or by evil spirits.
The apostle writes: “With patient endurance we run the race of faith set before us.” For what has more power than virtue? What has more firmness or strength than patient endurance? Endurance, that is, for God’s sake.
This is the queen of virtues, the foundation of virtue, a haven of tranquility. It is peace in time of war, calm in rough waters, safety amidst treachery and danger. It makes those who practice it stronger than steel.
No weapons or brandished bows, no turbulent troops or advancing siege engines, no flying spears or arrows can shake it.
Not even the host of evil spirits, not the dark array of hostile powers, nor the devil himself standing by with all his armies and devices will have power to injure the man or woman who has acquired this virtue through Christ.
(Letters 111, 35: PG 79, 401-404)