The Golden Rule Hinduism
‘Never do to others what would pain you’
Panchatantra 3.104		 Buddhism
‘Hurt not others with that which hurts yourself.’
Udana 5.18		 Zoroastrianism
‘Do not to others what is not well for oneself.’
Shayast-na-shayast 13.29
Jainism
‘One who neglects existence disregards their own existence’
Mahavira		 Confucianism
‘Do not impose on others what you do not yourself desire.’
Analects 12.2		 Taoism
‘Regard your neighbour’s loss or gain as your own loss or gain.’
Tai Shang Kan Ying Pien		 Baha’I
‘Desire not for anyone the things you would not desire for yourself.’
Baha’Ullah 66
Judaism
‘What is hateful to you do not do to your neighbour.’
Talmud, Shabbat, 31a		 Christianity
‘Do unto others as you would have them do unto you’.
Matthew 7.12		 Islam
‘Do unto all people as you would they should do to you.’
Mishkat-el-Masabih		 Sikhism
‘Treat others as you would be treated yourself.’
Adi Granth

Thanks to http://wecan.be/ for this fine summary.

(Not sure I always do this … – P.)

Thanks to S.