Our holy fathers have renounced all other spiritual work and concentrated wholly on this one doing, that is, on guarding the heart, convinced that, through this practice, they would easily attain every other virtue, whereas without it not a single virtue can be firmly established.
St. Symeon the New Theologian
Humility is the only thing we need; one can still fall having virtues other than humility -- but with humility one does not fall.
