It is customary for Buddhists to feed monks, if possible in one's own home, at certain fixed intervals of time after the death of a relative. In Sinhala these are all called mataka dānēs, meaning that they are given for the dead(1).  Though the food is offered to the monks with the thought that their consuming it is tantamount to its being consumed by the preta(s), giving to the Saṅgha and transferring the merit of that act came to be seen as more reliable than the simple act of providing food and drink. The stated purpose of the Petavatthu was 'to establish the superior merit of making gifts to the Buddhist Holy Order and their efficacy as a means of releasing the pretas from their state of woe'(2).  The 'transfer' is making a statement (aloud or sotto voce) in which the person who is 'making' merit, for example by giving food to the Saṅgha, calls the attention of a third party, such as the ghost (preta) of a recently dead family member, to what is going on, so that the preta uses this opportunity to empathise with the donor and enter into the same state of mind, thinking 'How I would like myself to be offering food to the Saṅgha!'

While a preta has little or no opportunity to perform meritorious actions independently, its(3)  acquisition of merit through a thought process is not confined to a ritual occasion. In the Majjhima Nikāya, in a list of recommendations of how a monk should behave, the Buddha says: 'If a monk should wish that it bring great advantage to his dead kinsmen to recollect him with faith in their hearts, he should fulfil the precepts, ... not neglect meditation ...'(4)  and the commentator says: 'If the dead relative acquires faith in the virtue of his monastic kinsman and just recollects him, that is capable of keeping the deceased from an evil rebirth for many thousands of kalpas and causing him finally to reach the deathless state'(5).  This surely added a new dimension to the 'transfer of merit'.

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The technique which permits the gods to acquire merit is virtually the same as is applied to the recently dead. The intended results, however, are different: the gods in return are supposed to give people protection and grant their wishes for this life. So, the positive functions which Brahmin/Hindu ideology ascribes to ancestors (though gods may share these functions as well), are firmly assigned by the Buddhists to gods. In the Buddhist interaction with pretas, however, the benefits flow the other way.

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In the nineteenth and twentieth centuries the Westerners, often agents of the Christian colonial powers, who first observed Buddhist societies were in many cases seriously confused. Finding that local Buddhist populations believed in gods and interacted with them, they criticized them for being bad Buddhists who had lost sight of the Buddha's teachings. Only until quite recently, when scholars began to point out that in the earliest scriptures, notably the Pali Canon, gods played a similar role to that which they play today, did they come to realize their misunderstanding; but this clarification has still not reached all the authors of textbooks and works of reference.

The practice of transferring merit led to a watershed in the history of Buddhism. Originally, one could only receive merit by wanting to do so and empathizing with an act of merit which one knew about. But in the Mahāyāna the standard way of transferring one's own act of merit was by expressing the wish that it accrue to the credit of all living beings - whether they were aware of it or not. The crucial link between karma and intention was thus broken. Merit could still be created by a meritorious intention, but over and above this it also floated around the universe in a way reminiscent of how we imagine luck.

The proliferation of the transfer of merit created the salient features which have characterized Mahāyāna Buddhism ever since. If one could so easily acquire merit through some act of empathy, without even being aware of it, this weakened the rigour of the Buddha's teaching that we are solely and wholly responsible for our own karma. In the Mahāyāna, supernatural figures, whether called Buddhas, bodhisattvas or gods, could both acquire and distribute merit as they pleased, and could do this in any situation anywhere in the universe. A comparativist may be forgiven for claiming that despite obscuring the cosmology by introducing many categories of living beings and sophisticated ontologies, Mahāyāna Buddhism became a polytheism.(6) 

 

6 Whether one calls non-Mahāyāna Buddhism ’theistic’ is really a matter of choice: certainly it believes in the existence of ’gods’, but no less certainly those gods are very unlike the beings that non-Buddhist theists normally believe in.