Possible Clues:

• 'Mouth quiet' is first of tenets for him
• Monk sounds drunk on gin
• One's speechless following order?
• Time right to meet a very quiet one, saint and monk
• Austere (and silent) monk
• Contemplative beer producer, Italian, takes soft drink, preposterously
• One who'd need his mouth sealed off to become holy saint?
• Retiring role mine, keeping shtoom for a start?
• Member of an order of monks noted for austerity and silence
• Man who silently obeys order