The Golden Rule is a moral which says treat others as you would like them to treat you. This moral in various forms has been used as a basis for society in many cultures and civilizations. It is called the 'golden' rule because there is value in having this kind of respect and caring attitude for one another.

People of many religions see the value of this mandate and have similar expressions. In Christianity, Jesus Christ taught this idea to his disciples and others when he gave his Sermon on the Mount. It is recorded in the Holy Bible in the book of Matthew, Chapter 7 and verse 12. Jesus explained to his listeners that all the things that were recorded in the Jewish law and that the prophets had taught about concerning morality was summed up in this one rule. The context of this statement (Matthew 7) is about God's mercy and kindness. The principle that was shared is to not always treat others as they might deserve to be treated, as we may judge some as undeserving, but instead to always be merciful and charitable, not withholding good.

In other religions and belief systems there is a similar concept of "the ethic of reciprocity", also called the Golden Rule. They usually give a similar idea, although sometimes it has been expressed in the form such as "Do not treat others as you would not like to be treated."

One of the earliest rules of this type is from the Old Testament days of Moses: "Love thy neighbor as thyself" (Leviticus 19:18).  Similar rules have also appeared over time: 

 ca. 950 BC: "...by making dharma (right conduct) your main focus, treat others as you treat yourself." - Mahabharata Shānti-Parva 167:9 (Hinduism)
 ca. 600 BC: "Avoid doing what you would blame others for doing." – Thales (Greek philosopher)
 ca. 500 BC: "Hurt not others in ways that you yourself would find hurtful." - Buddha Udanavarga 5:18 (Buddhism)
 ca. 500 BC: "A man should wander about treating all creatures as he himself would be treated." — Sutrakritanga, 1.11.33 (Jainism)
 ca. 480 BC: "Is there any one word that could guide a person throughout life?" The Master replied: "How about 'shu' [reciprocity]: never impose on others what you would not choose for yourself?" - Confucius Analects 15:24
 ca. 400 BC: "Do not do to others that which angers you when they do it to you." - Isocrates (Greek philosopher)
 ca. 350 BC: "That which you hate to be done to you, do not do to another." - Egyptian Papyrus, Brooklyn 47:218:135 
 ca. 50 BC: "What you do not want to happen to you, do not do it yourself either." - Sextius (Greek philosopher)
 ca. 1 AD: "Do not do to others what you know has hurt yourself" - Tirukkural (Tamil Hinduism) 
 ca. 400 AD: "What is hateful to you, do not do to your fellow: this is the whole Torah; the rest is the explanation..." - Babylonian Talmud Shabbath 31:a (Judaism)
 ca. 600 AD: "None of you [truly] believes until he wishes for his brother what he wishes for himself." - Muhammad, various hadiths (Islam)
 ca. 800 AD: "Whatever is disagreeable to yourself, do not do unto others." Shayast-na-Shayast 13:29 (Zoroastrianism)
 ca. 1200 AD: "Regard your neighbor's gain as your own gain, and your neighbor's loss as your own loss." Treatise on the Response of the Tao (Taoism)
 ca. 1400 AD: "If the entire Dharma can be said in a few words, then it is — that which is unfavorable to us, do not do that to others." Padmapuraana 19/357–358 (Hinduism)
 ca. 1850 AD: "And if thine eyes be turned towards justice, choose thou for thy neighbour that which thou choosest for thyself." Baha'ullah (Baha'i Faith)

Related pages 
Quid pro quo is when a return favour is definitely expected.

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