Sivan 5717.
The mitzvah of milah as fulfilled by Avraham Avinu was also in a physical sense.
Moreover, this is actually a primary intention within the mitzvah, as written in the discourse "Hinei Avram" (Torah Or, beginning of Lech Lecha) section 65, and in Likkutei Torah on Parshas Behar, in the explanation there (page 86a).
Summary
The Rebbe teaches that Avraham’s observance of milah was not merely spiritual but involved actual physical action, emphasizing that the essence of mitzvos is their performance in the physical world.