PAST LIFE REGRESSION AND KARMA THEORY....

KARMA
(Sanskrit: कर्म[1] IPA: [ˈkarmə] (Pali: kamma) in Indian religions is the concept of "action" or "deed", understood as that which causes the entire cycle of cause and effect (i.e., the cycle called saṃsāra) originating in ancient India and treated in the Hindu, Jain, Buddhist, and Sikh religions.

ORIGINS
A concept of karma (along with samsara and moksha) may originate in the shramana tradition of which Buddhism and Jainism are continuations. This tradition influenced the Brahmanic religion in the early Vedantic (Upanishadic) movement of the 1st millennium BC. This worldview was adopted from this religious culture by Brahmin orthodoxy, and Brahmins wrote the earliest recorded scriptures containing these ideas in the early Upanishads. Until recently, the scholarly consensus was that reincarnation is absent from the earliest strata of Brahminical literature. However, a new translation of two stanzas of the Rig Veda indicate that the Brahmins may have had the idea, common among small-scale societies around the world, that an individual cycles back and forth between the earth and a heavenly realm of ancestors. In this worldview, moral behavior has no influence on rebirth. The idea that the moral quality of one's actions influences one's rebirth is absent from India until the period of the shramana religions, and the Brahmins appear to have adopted this idea from other religious groups.
HINDUISM
Many Hindus see God's direct involvement in this process; others consider the natural laws of causation sufficient to explain the effects of karma. Followers of Vedanta consider Ishvara, a personal supreme God, as playing a role in the delivery of karma. Theistic schools of Hinduism such as Vedanta thus disagree with the Buddhist and Jain views and other Hindu views that karma is merely a law of cause and effect but rather is also dependent on the will of a personal supreme God. A summary of this theistic view of karma is expressed by the following: "God does not make one suffer for no reason nor does He make one happy for no reason. God is very fair and gives you exactly what you deserve."
Karma is not punishment or retribution but simply an extended expression or consequence of natural acts. Karma means "deed" or "act" and more broadly names the universal principle of cause and effect, action and reaction, that governs all life. The effects experienced are also able to be mitigated by actions and are not necessarily fated. That is to say, a particular action now is not binding to some particular, pre-determined future experience or reaction; it is not a simple, one-to-one correspondence of reward or punishment.
Karma is not fate, for humans act with free will creating their own destiny. According to the Vedas, if one sows goodness, one will reap goodness; if one sows evil, one will reap evil. Karma refers to the totality of our actions and their concomitant reactions in this and previous lives, all of which determines our future. The conquest of karma lies in intelligent action and dispassionate response.
One of the first and most dramatic illustrations of Karma can be found in the Bhagavad Gita. In this poem, Arjuna the protagonist is preparing for battle when he realizes that the enemy consists of members of his own family and decides not to fight. His charioteer, Krishna (an avatar of god), explains to Arjuna the concept of dharma (duty) among other things and makes him see that it is his duty to fight. The original Hindu concept of karma was later enhanced by several other movements within the religion, most notably Vedanta, and Tantra.
In this way, so long as the stock of Sanchita karma lasts, a part of it continues to be taken out as Prarabdha karma for being experienced in one lifetime, leading to the cycle of birth and death. A jiva cannot attain moksha until the accumulated sanchita karmas are completely exhausted.
BUDDHISM
In Buddhism, karma (Pāli kamma) is strictly distinguished from vipāka, meaning "fruit" or "result". Karma is categorized within the group or groups of cause (Pāli hetu) in the chain of cause and effect, where it comprises the elements of "volitional activities" (Pali sankhara) and "action" (Pali bhava). Any action is understood as creating "seeds" in the mind that will sprout into the appropriate result (Pāli vipaka) when met with the right conditions. Most types of karmas, with good or bad results, will keep one within the wheel of samsāra, while others will liberate one to nirvāna.
Karma is one of five categories of causation, known collectively as niyama dhammas, the first being kamma, and the other four being utu (seasons and weather), bīja (heredity, lit. "seed"), chitta (mind) and dhamma (law, in the sense of nature's tendency to perfect).
SPIRITISM
In Spiritism, karma is known as "the law of cause and effect", and plays a central role in determining how one's life should be lived. Spirits are encouraged to choose how (and when) to suffer retribution for the wrong they did in previous lives. How we know of this without remembering we had the choice is ambiguous. Disabilities, physical or mental impairment or even an unlucky life are due to the choices a spirit makes before reincarnating (that is, before being born to a new life).
What sets Spiritism apart from the more traditional religious views is that it understands karma as a condition inherent to the spirit, whether incarnated or not: the consequences of the crimes committed by the spirit last beyond the physical life and cause him (moral) pain in the afterlife. The choice of a life of hardships is, therefore, a way to rid oneself of the pain caused by moral guilt and to perfect qualities that are necessary for the spirit to progress to a higher form.
Because Spiritism always accepted the plurality of inhabited worlds, its concept of karma became considerably complex. There are worlds that are "primitive" (in the sense that they are home to spirits newly born and still very low on intellect and morals) and a succession of more and more advanced worlds to where spirits move as they are elevated. A spirit may choose to be born on a world inferior to his own as a penance or as a mission.