From the Evergetinos

An Elder said: Humility has often saved many, even without effort; this is demonstrated by the Publican and the Prodigal Son, who said only a few words and were saved.

Abba Isaiah said: "We need humility more than any other virtue; let us always be ready, whatever word we might say or hear, or whatever we might do, to say 'forgive me'; for through humility, all of the evil works of the Devil are foiled."

Evergetinos (I.XLIV.8,10)