Likkutei Sichos Vol. 29 Shoftim 3.

What happens when someone’s behaviour gives us every reason to see them negatively? In this class, we explore a surprising law of the Sanhedrin and the Rebbe’s deeper message: what we see in a person may be true, but it may still not be the whole truth. Torah teaches that even when the good in someone is completely hidden, it is still there — and the way we see and speak about a person can help bring that good back to the surface.