While acknowledging the fruits of prayer in many places at various times, Pope Francis also points to the Carmelite saint for advice to keep to oneself regularly to fuel and foster prayer at other times.
149. For this to happen, however, some moments spent alone with God are also necessary. For Saint Teresa of Avila, prayer “is nothing but friendly intercourse, and frequent solitary converse, with him who we know loves us”. [Autobiography, 8, 5]
The retreat movement is rich, fruitful, and praiseworthy in Catholicism, but I think the silent retreat is overlooked as a need. I’ve experienced many fine retreats in groups, but sometimes the social component can overpower the possibilities for spiritual encounter.
St John Paul suggests that silence is not just for those who live within a vow of silence:
I would insist that this is true not only for a privileged few, but for all of us, for “we all have need of this silence, filled with the presence of him who is adored”. [John Paul II, Apostolic Letter Orientale Lumen 16] Trust-filled prayer is a response of a heart open to encountering God face to face, where all is peaceful and the quiet voice of the Lord can be heard in the midst of silence.