Christianity
"So then, whatever you desire that others would do to and for you, even so do also to and for them, for this is (sums up) the Law and the Prophets." (Matthew 7:12, Amplified)
Confucianism
"Do not do to others what you would not like yourself. Then there will be no resentment against you, either in the family or in the state." (Analects 12:2)
"Try your best to treat others as you would wish to be treated yourself, and you will find that this is the shortest way to benevolence." (Mencius VII.A.4)
"Tsekung asked, 'Is there one word that can serve as a principle of conduct for life?' Confucius replied, 'It is the word shu--reciprocity: Do not do to others what you do not want them to do to you.'" (Analects 15.23)
Buddhism
"Hurt not others in ways that you yourself would find hurtful." (Udana -Varga 5,1)
"Comparing oneself to others in such terms as 'Just as I am so are they, just as they are so am I,' he should neither kill nor cause others to kill." (Sutta Nipata 705)
"The Ariyan disciple thus reflects, Here am I, fond of my life, not wanting to die, fond of pleasure and averse from pain. Suppose someone should rob me of my life... it would not be a thing pleasing and delightful to me. If I, in my turn, should rob of his life one fond of his life, not wanting to die, one fond of pleasure and averse from pain, it would not be a thing pleasing or delightful to him. For a state that is not pleasant or delightful to me must also be to him also; and a state that is not pleasing or delightful to me, how could I inflict that upon another? As a result of such reflection he himself abstains from taking the life of creatures and he encourages others so to abstain, and speaks in praise of so abstaining." (Samyutta Nikaya v.353)
Hinduism
"This is the sum of duty; do naught onto others what you would not have them do unto you."
(Mahabharata 5,1517)
"One should not behave towards others in a way which is disagreeable to oneself. This is the essence of morality. All other activities are due to selfish desire." (Mahabharata, Anusasana Parva 113.8)
Islam
"None of you [truly] believes until he wishes for his brother what he wishes for himself." (Number 13 of Imam "Al-Nawawi's Forty Hadiths)
"The Prophet said, 'None of you will have faith till he wishes for his (Muslim) brother what he likes for himself.'" (Bukhari 1.2.12)
Judaism
"What is hateful to you, do not do to your fellowman. This is the entire Law; all the rest is commentary." (Talmud, Shabbat 3id)
"You shall love your neighbor as yourself." (Leviticus 19.18)
Taoism
"Regard your neighbor's gain as your gain, and your neighbor's loss as your own loss."
(Tai Shang Kan Yin P'ien)
Zoroastrianism
"That nature alone is good which refrains from doing another whatsoever is not good for itself."
(Dadisten-I-dinik, 94,5)
Jainism
"A man should wander about treating all creatures as he himself would be treated." (Sutrakritanga 1.11.33)
"One who you think should be hit is none else but you. One who you think should be governed is none else but you. One who you think should be tortured is none else but you. One who you think should be enslaved is none else but you. One who you think should be killed is none else but you. A sage is ingenuous and leads his life after comprehending the parity of the killed and the killer. Therefore, neither does he cause violence to others nor does he make others do so." (Acarangasutra 5.101-2)
African Traditional Religions
"One going to take a pointed stick to pinch a baby bird should first try it on himself to feel how it hurts." (Yoruba Proverb -Nigeria)