Baha'i Faith:  Baha'u'llah,Gleanings
Lay not on any soul a load that you would not wish to be laid upon you, and desire not for anyone the things you would not desire for yourself.

Buddhism:  The Baddha, Udana-Varga 5.18
Treat not others in ways that you yourself would find hurtful.

Christianity:  Jesus, Matthew 7:17
In everything, do to others as you would have them do to you; for this is the law and the prophets.

Confucianism:  Confucius, Analects 15.23
One word which sums up the basis of all good conduct: loving-kindness. Do not do to others what you do not want done to yourself.

Hinduism:  Mahabharata 5:15-17
This is the sum of duty: do not do to others what would cause pain if done to you.

Islam:  The Prophet Muhammad, 13th of the 40 Hadiths of Nawawi
Not one of you truly believes until you wish for others what would cause pain if done to you.

Judaism:  Hillel, Talmud, Shabbath 31a
What is hateful to you, do not do to your neighbor. This is the whole Torah, all the rest is commentary. Go and learn it.

Sikhism:  Guru Granth Sahib, pg. 1299
I am a stranger to no one; and no one is a stranger to me. Indeed, I am a friend to all.

Taoism:  Lao T'zu, T'ai Shang Kan Ying P'ien, 213-218
Regard your neighbor's gain as your own gain and your neighbor's loss as your own loss.

Unitarianism:  Unitarian principle
We affirm and promote respect for the interdependent web of all existence of which we are a part.

Zoroastrianism:  Shayast-na-Shayast 13.29
Do not do to others whatever is injurious to yourself.