Rashi famously quotes a Midrash at the beginning of Parshat Behar — which launches its discussion of the Sabbatical year by associating it with Mount Sinai — “What is the connection between Shemittah and Mount Sinai?”

The Midrash goes on to propose that just as the general concepts and precise details of Shemitta were handed down at Mount Sinai, so too every mitzva was given in general terms and with all the details at Mount Sinai.

The commentaries all have a field day with this Midrash, trying to understand why the Torah particularly chose Shemitta as opposed to any other mitzva to make this point. Rabbi Dunner offers some intriguing and powerful ideas that have been suggested by a selection of recent rabbinic commentaries, including Rav Yehuda Amital z”l and the Lubavitcher Rebbe z”l.