Whatever service you do the benefit goes into your spiritual bank balance and it is kept there eternally! Even if later you give up devotional service: That stays in your bank balance!
It's not only the service is going into the spiritual bank balance but there is also interest! And that interest is not just an ordinary percentage like 4% or something like that...No...The interest percentage is unlimted because it says whenever Krishna remembers the service his appreciation increases...Krishna, He never forgets, He is eternal and His memory is eternal so His appreciation is going on eternally for all serivce done so the interest for the service that we are getting is unlimitedly increasing! So this is the nature of Krishna!
(HH KKS 31/08/2002)