The Golden Rule

"Do to no one what you would not wish others to do to you."
Confucius
"Do no impose on others what yourself do not desire."
Analects of Confucius 15:23
"Do naught to others which, if done to thee, would cause thee pain: this is the sum of duty"
Mahabharata 5:1517
"Thou shalt love thy neighbor as theyself"
Leviticus 19:10
"Whatever you wish that men would do to you, do so to them."
Matthew 7:12

But, we all know how very difficult this is.
I copied this down by hand years ago and recently found it in my stacks of notes and research. So, I'm not sure the spelling and references are accurate. You get the point.