Buddhism, an outline of its teachings and schools, p. 52-54
Karma in Buddhism
Hans Wolfgang Schuman
Our present existence is the result of deeds performed by ourselves in previous existences. The body is an 'old deed'(S 12,37, 3 II p. 65 - ), and to suffer means to endure kammic [karmic]effects, that is to lie on the bed one has made. Our future forms of existence are determined by our actions of today; we are now laying the foundations of our future 'fate'. Kamma [karma] in the view of Hinayana is a neutral law that admits no exception or interference, but of which,by acting accordingly, man can avail himself in order to obtain the rebirth wished for. No need to mention that even the happiest rebirth is not yet liberation.
It would be quite wrong to interpret the doctrine of kamma along deterministic lines. Only the quality, that is the social surrounding, the physical appearance and the mental abilities of a person are fixed by the deeds of his previous existences, but in noway his actions. Without cognising free will as a philosophical problem, Gotama takes it for granted that the innate character of each being leaves him the freedom to decide about the actions which determine his future.
Wholesome deeds help man to achieve better rebirth and thus bring him nearer to salvation; they do not, however, lead straight to liberation, to riddance of all rebirth. Deeds are something finite and cannot bear fruit beyond the finite. Even the best obtainable form of existence still lies within the cycle of rebirths. Nevertheless, Gotama does not disapprove of action in general:
I teach action ... as well as non-action ... I teach the non-performance of bad deeds with body ... speech and thought, of the many bad, unwholesome things ... I teach the performance of good deeds with body ... speech and thought, of the many wholesome things.
(A 2,4,3 I p. 62 - )
But if wholesome actions entangle man as much in samsara as unwholesome deeds, how should one act? Is it advisable, is it at all possible, to abstain from all action?
The Buddha's answer is a psychological one. It is not the action in itself, he explains, which determines the kammic future,but its motive, the mental attitude preceding it: Not the execution of the action but the action-intention (sankhara or cetana) shapes future existence. Supposing somebody is prevented from executing an intended action by outer circumstances: The bare action-intention suffices to produce the corresponding kammic effect. Only those deeds are free from kammic results which the seeker for liberation performs without greed, hatred and delusion.
Whatever deed, monks, has been performed without greed,without hatred and free from delusion ... after greed, hatred (and)delusion were done away with - this deed is annihilated, cut off at the root, made similar to a rooted-out palm tree, prevented from becoming(i.e. kammic ripening), in future not subject to the law of becoming.
(A 3,33,2 I p. 135 - )
This is the Buddhist way to liberation: to act but without greed for success, free from the wish to harm anybody and with reason.If there were no possibility of performing good deeds without becoming bound by kamma, the enchainment of man with samsara would be indissoluble, and he would have no chance of ever escaping from suffering.
The fact that the rebirth-existence is determined more by the mental attitude of the doer than by the actual deed furthermore entails that the same deed may yield different effects with different persons. An action which influences an ethically unstable person for a long time in a negative way may in the case of an ethically sound person be confined to minimal effects. A lump of salt in a cup make sits contents undrinkable, the same amount of salt in the river Ganges leaves the water as it was. (A 3, 99 I p. 249 ff. - )
 Samyuttanikaya, PTS edition
 Anguttaranikaya, PTS edition