Our Gemara on Amud Aleph discusses the concept of Meis Mitzvah, an abandoned body with no identifiable relatives. In such a case, even a Cohen Godol and a Nazir are permitted to tend to the burial.
Sefer Chassidim (261) says that metaphorically speaking, there are mitzvos which are neglected and abandoned and also are considered to be a Meis Mitzvah. Chofetz Chaim (Shemiras Halashon I:3) adds: This is true by force of a kal v’chomer. If a lifeless body that once held a soul overrides all other considerations and takes priority, surely neglected mitzvos, which remain imbued with a soul, must take priority!
The Chofetz Chaim said it in regard to sins of speech, which he considered to be long neglected. Sefer Chasidim used it in reference to certain mesechtos that were not studied frequently. While those examples may still be true, what other mitzvos cry out for our attention in today’s social climate?