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I know that there is very well known ritual called Ganga-snan in north-east Indian states and Bangladesh. It is said that If you bath in river Ganga, then all sin that you have done, are removed. But why? Because all human must suffer his karmaphala according to his/her karma. No one are above from this. And also in astrology, no one can change his destiny/bhagya. Then why this ritual is so well known? Why?