Sastras teach that by practising good deeds it is possible to lessen the sinful effects of bad karma. Sin accrues easily in our lives, knowingly and unknowingly, even as dust accumulates despite constant cleaning. It does not require any conscious effort for dust to settle down on cleaned surfaces. So practice of punya karma is advised as a step in cleaning or ridding us of the sinful effects of our bad karma, pointed out Sri Kesava Dikshitar in a discourse.
In the Gita, it is clearly shown that all beings are subject to the subtle impressions or vasanas of previous experiences in past lives. These become manifest as distinctive likes and dislikes in their successive births. People tend to think that whatever causes the experience of joy is good and is to be desired and that whatever causes sorrow is bad and has to be avoided. For instance, the vasana for tasting a particular dish or drink drives one to satisfy this desire and this becomes a habit which is difficult to break. The vasana is strong in the mind of the person. If properly analysed, there is no joy or merit in that dish, or for that matter any object in the world however attractive it may appear to us. But owing to the vasanas that are strong and can easily sway the mind, people are instigated to go after these worldly attractions. This leaning to the objects of the world is present right from birth and is the cause of delusion.
Accumulation of punya karma through several births can help to weaken the strong feelings of like and dislike and thus free them from this fundamental delusion. One has to be wary of both likes and dislikes that prevent one from gaining true wisdom. With the withdrawal of sin, the delusion caused by the pairs of opposites goes away, says Krishna in the Gita.
