Kamma produces its results in different ways. There are two general ways in which it comes to fruition:
1. It produces the type of rebirth, the basic rebirth consciousness.
2. It produces various results within the course of an existence..
At the time of death, a particular dominant kamma may come to the fore of the mind and steer the stream of consciousness to the new existence. Once rebirth takes place, certain other kammas mature during the course of life bringing either favourable or unfavourable results.
The good and bad results that arise from kamma are not rewards or punishments. They are not imposed by any outside power. Actions produce their results naturally through the law of cause and effect working in the moral realm. This natural law is called 'kamma niyama', the order of kamma, which functions autonomously. The Buddha explains how kamma is the cause of differences in the fortunes of people.
(a) Some people die prematurely because in the past they have destoyed life. The karmic result of killing is to be shortlived. Others live long because they were kind and compassionate, they had respect and reverence for life.
(b) Some are sickly because they have injured and hurt other beings.
(c) Those who were often angry and harsh become ugly, those who were patient and cheerful become beautiful.
(d) Some are rich because they have been generous in the past, some are poor because they have been selfish.
(e) Some are influential because they have rejoiced in the good fortunes of others.
(f) Some are weak and powerless because they have been envious of the good fortunes of others.
(g) Some are intelligent because they have been reflective and studious in the past, because they always enquired and investigated matters. Some are dull and stupid because they have been lazy and negligent, because they never studied and did not think.