He is a practicing Quaker. This is a traditional Quaker meeting in which the participants sit in silence, and perhaps raise to speak whenever the spirits moves them.
Silence is a form of speech.
From the silence, a person may feel the need to express real words of the heart. The 100 people shift on their folding plastic chairs for comfort. Many sit with legs crossed, relaxed, slouched, rather than in the proscribed spine-straight meditative posture with both feet flat on the ground. The silence that settles is not as dense has that which often accompanies a more formal meditation. The silence is a more open and inviting, rather than a box of quietude around each person.