Proverbs 24:28-29

28 Do not be a witness against your neighbor without cause, and do not deceive with your lips.
29 Do not say, "I will do to others as they have done to me; I will pay them back for what they have done."
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.