‘Karma’ means ‘activity.’ The law of karma is the natural law of action and reaction – in physics this is expressed by Newton’s 3rd law, “For every action there is an equal and opposite reaction.”
It should be noted here that all souls are essentially good. This means that just because someone gets a bad reaction it does not mean that they are a bad person. Another important point is that karma is temporary. This means that although we may be experiencing a particular set of circumstances right now, good or bad, those circumstances will change in the future.
Not only is karma temporary, but it is also possible to change one’s karma, or even get rid of it altogether.
Karma (good or bad) creates a cycle by which one is entangled in repeated action and reaction. As long as one is in this cycle one will experience both happiness and distress. The Vaishnava tradition teaches how one can break this cycle and achieve real liberty and real happiness.
In the Vaishnava tradition the concept of karma is intimately related to Reincarnation.