LET THE ONE WHO IS KIND CAST HIM OUT
The lesson from this applies to one who encounters a Jew and sees in him something lowly and unbecoming, G-d forbid, seeing him as an outcast, not worthy to be among the encampment of the Jewish people, G-d forbid. In that situation, the Torah states that prior to rendering this ruling upon another Jew, even a great sage must first make a proper self-assessment of where is he holding in kindness and love of a fellow Jew. * Likkutei Sichos Vol. 27, pg. 88-91