Chapter One - Mishna 6 (3)

And judge everyone favorably
Yehoshua ben Perachya ends by saying: "Judge every person in a good way." If you see a person doing something, and are not sure if he is doing right or wrong, judge him "l'kaf z'chus". Give him the benefit of the doubt. This boy is only willing to look at the good side of people. He is closing his eye and ignoring the bad points. If we get in the habit of judging people in a good way, Hashem will also judge us that way.

The Pirkei Avos series was developed by Pirchei Shoshanim