The Essentials of Teshuva According to Rav Soloveitchik: Tehillim 51

Sin has two aspects according to Rav Joseph B. Soloveitchik - the sin itself which necessitates punishment and the stain it causes on the soul - even his halachic personality changes. The first aspect requires כפרה (atonement); the second aspect requires purification (טהרה). This is why King David asks God not just for forgiveness but also to be purified (טהרני).

Delivered at the OU Israel Center, August 28th, 2018 (17 Av 5778)