Instead of judging the other person, simply judge the actions by their results. And then turn around and look at yourself, at the things you do and say: Are those unskillful words and actions to be found in you?

"When looking at people around you, it’s important that you get away from your sense of competitiveness, of this person versus that person. You look, not at them, but at their activities. Otherwise you start comparing yourself to the other person: “This person’s better than I am. That person’s worse than I am.” And that brings in questions of conceit, resentment, and competition, which are not really helpful because we’re not here to compete with each other. We’re here to work on ourselves. So again, look at other people simply in terms of their thoughts, their words, their actions. And see what’s an admirable action, what are admirable words, what are admirable ideas, ones you can emulate, ones you can pick up. In this way the fact that we’re living together becomes a help to the practice rather than a hindrance.

The same is true when you notice people around you doing things that are not so admirable. Instead of judging the other person, simply judge the actions by their results: that that particular action, that particular way of thinking or speaking is not very skillful, for it obviously leads to this or that undesirable result. And then turn around and look at yourself, at the things you do and say: Are those unskillful words and actions to be found in you? Look at the behavior of other people as a mirror for your own behavior. When you do this, even the difficulties of living in a community become an aid to the practice."

~ Thanissaro Bhikkhu "Admirable Friendship" (Meditations1)