Silence preserves

“When the door of the steambath is continually left open, the heat inside rapidly escapes through it; likewise the soul, in its desire to say many things, dissipates its remembrance of God through the door of speech, even though everything it says may be good. Thereafter, the intellect, though lacking appropriate ideas, pours out a welter of confused thoughts to anyone it meets.”
— St Diadochos of Photiki

“Silence is a mystery of the age to come, but words are instruments of this world.”
— St Isaac the Syrian