Integrity Defines a Jew
Callousness towards others' feelings is a frequent cause of chillul Hashem.
Rashiand Rebbeinu Yonah's commentaries on zechiras Amalek.
Analysis of the differences between lacking yiras shomayim in private, versus being a fraud in one's essence: an emunah problem versus amiddos problem.
Discussion of the blindness to monetary dishonesty amongst some "frum" Jews.
The corruption of being ready and equipped to support evil – even before committing a sin.
Citations: In addition to the commentaries on Mishlei, this shiur references Rashi and Rabbeinu Bachye Devarim 25:17, Tosafos Kiddushin 33b.