This sugya explores the exoneration of one who commits an Aveira B'Oness. The source for this exemption is the puk in Parsh Ki Seitzei that states "v'lana'arah lo sa'eh davar". An aveira that one commits B'Shogeg (unintentionally) is still considered an aveira which requires a korban, while an Oness does not. However, there is still much discussion to whether one would still need a Kapara/Teshuva, and why. One proof of this concept is the fact that, in the Viduy on Yom Kippur we include aveiros that were done b'oness.
Tags: kapparas yom kippurim