Here's one. It's quote from F. Scott Fitzgerald's the Great Gatsby, and something I try to follow. I was disappointed it was changed and simplified in the movie to, "Always try to see the best in people." which is a similar thought, but not the same, since it doesn't include the part that takes into account people's different experiences.
Anyway, here it is:
In my younger and more vulnerable years my father gave me some advice that I've been turning over in my mind ever since. "Whenever you feel like criticizing any one," he told me, "just remember that all the people in this world haven't had the advantages that you've had.” ― F. Scott Fitzgerald, The Great Gatsby
(Explanation from SparkNotes) From the start of the novel, Fitzgerald presents the theme of differences between social classes and races in 1920’s America by having his narrator say, wisely, that it is not fair to judge people by circumstances over which they have no control. It’s important that Nick’s family (which is not rich, but financially comfortable) taught him this belief, as it paints him as a correct and respectable man, and thus encourages us to view him as a trustworthy and honest narrator. Therefore, we can expect — to an extent — anything that Nick says to be reasonable, including his criticism of people like Tom Buchanan, who love to criticize others precisely because they haven’t had the same advantages as he has.
I always try give people the benefit of the doubt. Sometimes it's very difficult to, but I always remind myself I don't know the whole story and I can't just judge them based on a singular instance. Like any other person, of course, I still have my biases and dislike certain people, but I try my best not to have that happen.