1. What do all eight religions share?
Reciprocity
reciprocity
What is “reciprocity”?

2. Hurt not others in ways that you yourself would find hurtful."
"Ethic of Reciprocity"
Buddhism: 
Hurt not others in ways that you yourself would find hurtful."
Udana-Varga 5:18

3. "Do unto others as you would have others do unto you"
"Ethic of Reciprocity"
Christianity: 
"Do unto others as you would have others do unto you"
Gospel of Matthew7:12

4. "Do not do to others what you do not want them to do to you"
"Ethic of Reciprocity"
Confucianism:
"Do not do to others what you do not want them to do to you"
Analects 15:23

5. Number 13 of Imam "Al-Nawawi's Forty Hadiths."
"Ethic of Reciprocity"
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."

6. Judaism: "...thou shalt love thy neighbor as thyself.“ Leviticus 19:18
"Ethic of Reciprocity"
Judaism: 
"...thou shalt love thy neighbor as thyself.“
Leviticus 19:18 

7. "Ethic of Reciprocity"
Hinduism:
"This is the sum of Dharma [duty]: Do naught unto others which would cause you pain if done to you".
Mahabharata, 5:1517 "

8. "The Sage...makes the self of the people his self."
"Ethic of Reciprocity"
Daoism
"The Sage...makes the self of the people his self."
—Dao De Jing

9. "No one is my enemy, none a stranger and everyone is my friend."
"Ethic of Reciprocity"
Sikhism:
"No one is my enemy, none a stranger and everyone is my friend."
Guru Arjan Dev : AG 1299