Throughout our lives, we are busily shaping another body, so that when our work here has been completed and we have to leave it, we go to the other body that we have been preparing with our actions in this one. In other words, once all the results of our activities in previous lives that were destined for this body have been suffered or enjoyed, then it is time to leave it. We give up this body in great distress, but when it falls away here in this world, we leave it with our subtle body and enter another body.

Wherever we go, we enjoy or suffer the consequences of our previous actions with the new set of external senses that we possess. Joy and suffering, happiness or distress. These are the workings of this world - jagad-vyapara - over which no one, not even the greatest scientist, has any control. This is a law that no one can challenge." (Srila Bhakti Promode Puri Maharaj, from 'Samadhi', Mandala Publishing)