Before you speak, it is necessary for you to listen, for God speaks
in the silence of the heart.  (Mother Teresa of Calcutta)

The Benedictine of Mary, Queen of Apostles, strives to be "silent by vocation, articulate by mission." (Dom Hubert Van Zeller) 

To cultivate an atmosphere for prayer, the sisters keep silent as they work. This silence is broken only to ask questions or give instructions concerning work. After Compline and until Prime the next day, the "Grand Silence" is maintained. All speech, except in cases of grave necessity, is forbidden at this time.

Everyday, there is a time allotted for speaking at recreation. Otherwise, in her conversion of life, each nun seeks to imitate Our Lady; who "remained, silent, in adoration of her Son... and from the sanctuary of her Immaculate Heart a hymn of praise and thanksgiving rose up unceasingly to God." (Bl. Columba Marmion)