This is a profound and simple explanation to Karma, which is the core of Buddhist believe. Live now to prepare for next life.
"In one's life time,one's life-style,actions,livelihood,and so on,are due to one's own doings and these will form a subsequent result.Such result may appear within a short time,or it may be delayed until the next life,in which case it is an inter-life result. The cause and effect of inter-life make it difficult for us to comprehend,leading to the view that Buddha's dharma is beyond common understanding.
Therefore people often say:"I have always been a good man,why do I have to suffer all these misfortunes?" The other man is ill-natured and all his undertakings are bad,yet why is he still living in luxury?"
Therefore it is important to know the dharma to understand that there is karma."