Individual said: If past rebirths are innumerable and the third type of karma exists, why should there not result in innumerable aeons of vipaka, even for an Arahant? In his past, he had innumerable lives where he generate all three kinds of karma, so how could any of it ever be exhausted?
Some wise words from Venerables Nyanaponika, Bodhi, and Brahmavamso ----
Kamma and Its Fruit - Venerable Nyanaponika Maha Thera
Most writings on the doctrine of kamma emphasize the strict lawfulness governing kammic action, ensuring a close correspondence between our deeds and their fruits. While this emphasis is perfectly in place, there is another side to the working of kamma - a side rarely noted, but highly important. This is the modifiability of kamma, the fact that the lawfulness which governs kamma does not operate with mechanical rigidity but allows for a considerably wide range of modifications in the ripening of the fruit.
If kammic action were always to bear fruits of invariably the same magnitude, and if modification or annulment of kamma-result were excluded, liberation from the samsaric cycle of suffering would be impossible; …….
Questions on Kamma – Bhikkhu Bodhi
Kamma is like a seed
First of all, not all Kamma has to ripen as a matter of necessity. Although it has the tendency to ripen, it does not ripen inevitably. Kamma is like a seed. Seeds ripen only if they meet the right conditions. But if they do not meet the right conditions they remain as seeds; if they are destroyed they can never ripen at all. Similarly, it can be said of kamma that kamma pushes for an opportunity to mature. It has a tendency to mature. If kamma finds the opportunity then it will bring its results. If it does not meet the right conditions it won't ripen. One kamma can even be destroyed by another kamma. So it is important to understand that our present way of life, our attitudes and conduct, can influence the way our past kammas mature. Some past kammas are so powerful that they have to come to fruition. We cannot escape them no matter what we do. But the greatest number of our past kammas are conditioned by the way we live now. If we live heedlessly, unwisely, we will give our past bad kammas the opportunity to ripen and this will either hinder the good kammas from producing their effects or else cancel out their good effects. On the other hand, if we live wisely now, we will give our good kammas the opportunity to mature and bar out our bad kammas or weaken them, destroy them or prevent them from coming to fruition
A little from Ajahn Brahms:
It is of interest now to look at the links that are not sufficient conditions.
Sankhara is not a sufficient condition for rebirth linking consciousness and the stream of consciousness that follows. This is because, having produced many rebirth-inclining kamma formations early on in one's life, it is possible to make them all null and void (called `ahosi kamma') with the attainment of arahant, which attainment eliminates the stream of consciousness that would otherwise begin at rebirth.
The fact that upadana is not a sufficient condition for bhava is similar to sankhara not being a sufficient condition for vinnana. Through the development of the Noble Eightfold Path as far as Full Enlightenment, no new upadana are generated and all previous upadana becomes ineffective in producing a ground for a new existence or bhava. The upadana previous to Full Enlightenment becomes, as it were, `ahosi upadana'.
Even more obvious, vedana is not a sufficient condition for tanha. vedana are certainly experienced by arahants, but they never generate tanha. Moreover, for ordinary people, not every vedana produces craving.
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