It is described in the Sixth Canto of the Srimad-Bhagavatam that real atonement does not mean to simply neutralize the effects of sinful reactions. One may try to neutralize the effects of the sinful reactions by engaging in some form of pious activity, such as performing austerities, giving charity or accepting vows. However, although the performance of pious activities neutralizes the reaction, these activities will not uproot the desires from within the heart to perform sinful activities again. Therefore, the Bhagavatam states that real freedom from reactions of sinful activities means to uproot the weeds of sinful desires within the heart—kecit kevalaya bhaktya. Just as the fog is gradually burned by the rays of the sun, in the same way, unalloyed devotional service to Krishna can uproot the weeds of sinful actions.
LFD Vol 3,Uprooting Sinful Activities, Pg 203, last paragraph onwards