Judge everybody favorably! (Avot 1:6). This promotes peace (Rashi).
One who judges others favorably, is himself judged favorably (Shabbat 127b).
Rebbe Nachman tells us that Hashem’s way is to focus on the good that we do. Even if there are things which are not so good, He only looks for the good, as it is written, “He does not look at evil in Yaakov” (Numbers 23:21). How much more do we have to avoid looking negatively at another person in order to find what is not good in them, to search for their shortcomings. We are obligated to look only for the good! (Likutei Moharan II: 17).
Adapted from Crossing the Narrow Bridge, by Chaim Kramer