Never underestimate the value of Tears.

 Tears are a very powerful tool.  When our tears come from the heart, they have a cleansing effect.  When we cry over our sins, they wash away our sins.  Even when a person does a big sin and does Teshuva there is still a stain on the person's neshamah.  True tears wash away this stain.

heard from a Shiur by Rebbitzin Kalmonovitz