Rabbi Abraham J. Twerski, MD introduces the importance of studying Pirkei Avos in his book, Visions of the Fathers (page 2):
Pirkei Avos – Ethics of the Fathers – is the favorite tractate of the Talmud. Although one is not to show preference for any particular part of the Torah, it is difficult not to single out Ethics of the Fathers as the choice of many people. …Indeed, even the Talmud singles out Pirkei Avos when it says, “If someone wishes to be truly pious, he should fulfill the teachings of Pirkei Avos (Bava Kama 30a)…The Midrash states that we were given Torah and mitzvos in order to refine ourselves (Vayikra Rabba 13:3). The many works of mussar and Chassidus concentrate on the development of middos (character traits), and the ultimate source of middos can be found in Ethics of the Fathers.
The 15th century commentator Rabbi Ovadiah MiBartenura sharply contrasts the Jewish source of character and ethics with the nations of the world. He writes that secular philosophers and thinkers have also written compendiums on personal development, yet Pirkei Avos begins by anchoring its own basis as Divine: Moshe received the Torah at Sinai.
Rabbi Moshe Goldberger has published a new eBook with important take-home lessons from Pirkei Avos Perek I: 4-7. Download the eBook here.