Topics discussed:

Why is the slave punished for his desire to stay longer? R. Shaul Yisraeli

Why isn't the slave's ear pierced when he first gets into trouble? The Maharil Diskin

The need to temporarlily return a collateral reflects an expansive view of the Torah's mandate.  R. Yechiel Yaakov Weinberg

Love the convert since you were strangers in Egypt is said immediately after they left Egypt;

Sensitivity when there's an open wound - you were strangers, not you were slaves.  R. Kenneth Hain from R. Sholom Carmy

We are reciepients of Divine gifts - sometimes He takes them back.  Rav Soloveitchik

Orphans and Widows.  R. Moshe Feinstein