The Four Agreements: A Practical Guide to Personal Freedom is by Miguel Ruiz.
There seems to be a theme of writing letters to those who’ve hurt you in order to heal oneself. If you could say anything to people from your past who have hurt you, what would you say? The last letter I wrote to those who hurt me followed the four principles detailed below. I hope you and those involved in hurting anyone read it and take it to heart. Because I think these are all important points to remember as we live out our lives in the present moment each and every day.
The First Agreement: Be impeccable with your word. Speak with integrity. Say only what you mean. Avoid using the word to speak against yourself or to gossip about others. Use the power of your word in the direction of truth and love.