We might have much peace if we would not busy ourselves with the sayings and doings of others, and with things which do not concern us. How can he remain long in peace who entangles himself with other peoples cares: who seeks occasions abroad, and who is little or seldom inwardly recollected? Blessed are the single-hearted for they shall enjoy much peace.
—Thomas a Kempis
An excerpt from The Imitation of Christ.