Christian:

Do unto others as you would have them do unto you. (Mt. 7:12)

Jewish:

What is hurtful to yourself, do not do to your fellow man.
That which is hurtful to thee do not to thy neighbor. (Hillel)

Muslim:

Do unto all men as you would wish to have done unto you; and reject for others what you would reject for yourselves. (Hadith)

Hindu:

Treat others as thou wouldst thyself be treated. Do nothing to thy neighbor which, hereafter, thou wouldst not have thy neighbor do to thee. (Mahabharata)

Buddhist:

Hurt not others with that which pains yourself. (Dhammapada)

Confucian:

What you do not yourself desire, do not put before others. (Analects)

Zoroastrian:

Whatever is disagreeable to yourself, do not do unto others.

Jain:

A man should wander about treating all creatures as he himself would be treated. (Sutrakritanga 1.11.33)

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)