Garlic as an edible substance was forbidden during the early sangha. It seems that at the time many people found it to be an utterly offensive substance and this was not limited to Buddhists. In the Vedic traditions as well we see a strong disdain for garlic as well as onions. For example, in the Manusmṛti (Laws of Manu), which admittedly dates a few centuries after the Buddha's lifetime, we see the following proscriptions:
5. Garlic, leeks and onions, mushrooms and (all plants), springing from impure (substances), are unfit to be eaten by twice-born men.
19. A twice-born man who knowingly eats mushrooms, a village-pig, garlic, a village-cock, onions, or leeks, will become an outcast.
The Buddhist Vinaya literature also prescribes strict rules against eating garlic, stating that it is only to be consumed medicinally and even then there are protocols in place to prevent the garlic eater from offending his fellow monastics with his odor by becoming something of a temporary outcast. Here I would like to look at some of the rules and regulations concerning garlic as it is found in the Indian Vinaya literature as translated and preserved in Chinese (much Indian Buddhist literature only survives in Classical Chinese I should note). At the same time I would like to point out how while garlic was considered disagreeable, the substance of cow dung was not. This kind of sensibility was largely held in common with Vedic traditions. This is also an interesting cultural difference to consider given that in modern times in the west and of course elsewhere it is the complete opposite.
To begin with, the Four Part Vinaya of the Dharmagupta school forbids the consumption of garlic, though the severity of the offense differs according to the gender.
《四分律》卷25：「若比丘尼噉生蒜熟蒜若雜蒜者咽咽波逸提。比丘突吉羅。式叉摩那沙彌沙彌尼突吉羅。是謂為犯。不犯者。或有如是病。以餅裹蒜食。若餘藥所不治。唯須服蒜差聽服。若塗瘡不犯。」(CBETA, T22, no. 1428, p. 737, b10-14)
“If a bhikṣuṇī (nun) eats raw garlic, old garlic or mixed garlic, it is a pāyattika offense when swallowed. For a bhikṣu (monk) it is a duṣkṛta (misdemeanor) offense. For a śikṣamāṇā, śrāmaṇera (male novice) or śrāmaṇerī (female novice) it is a duṣkṛta offense. This is considered a violation. A non-violation would be if someone had an illness as such and the garlic was eaten in a biscuit. If one cannot be cured with other medicines and only with treatment with garlic will one recover, then the treatment is permitted. If smeared on a skin sore there is no violation.”
The Sarvāstivādavinaya Saṃgraha offers the following protocol for a monastic taking garlic medicinally.
《根本薩婆多部律攝》卷8：「若服蒜為藥者。僧伽臥具大小便處。咸不應受用。不入眾中不禮尊像。不繞制底。有俗人來不為說法。設有請喚亦不應往。應住邊房服藥既了。更停七日待臭氣銷散。浴洗身衣並令清潔。其所居處牛糞淨塗。」(CBETA, T24, no. 1458, p. 571, a10-15)
“If treating [an illness] with garlic, neither the sangha bedding nor lavatory should be used. One does not enter in among the sangha. One does not prostrate to the Buddha or circumambulate caityas. If a laymember comes, one does not teach the Dharma. Even if requested one should not go. One should reside in a room on the periphery [of the monastery]. When the treatment of medicine is completed, one remains settled for a further seven days to wait for the odor to disperse. Washing the body and clothes making them pure, the place one stayed in is to be purified by smearing it with cow dung.”
Curiously the last eight characters as quoted in a Ming Dynasty (1368-1644) vinaya commentary have one slight modification where the “cow dung” is replaced with “sweeping”.
《四分戒本如釋》卷5：「其所居處。掃灑淨塗。」(CBETA, X40, no. 717, p. 237, b8-9 // Z 1:63, p. 60, d4-5 // R63, p. 120, b4-5)
“The place one stayed in is to be swept and purified by smearing.”
The Chinese here becomes ambiguous because what substance one is to smear the room with becomes unclear. The reader is left to use their imagination, which in Ming Dynasty China would probably have meant incense or some other agreeable substance and not cow dung as was the case in the original text. This modification in the text is quite significant because it speaks of vast cultural differences. In ancient India cow dung was considered a pure substance and even used medicinally, which the Buddha approved of according to the record.
The idea of “cleansing” a space with smeared cow dung is found in ancient Indic literature in general. For example, in the Śrīmad Bhāgavatam we see the following:
“First one should sweep and dust thoroughly, and then one should further cleanse with water and cow dung. Having dried the temple, one should sprinkle scented water and decorate the temple with mandalas.”
There is an account of the Buddha prescribing a form of panchgavya (otherwise called cowpathy in English) in the Mūlasarvāstivāda Nidāna Mātṛka as follows:
《根本說一切有部尼陀那目得迦》卷3：「佛言。有無齒牛食噉糠麥。後時便出其粒仍全。用此為麨非時應服。」(CBETA, T24, no. 1452, p. 427, b18-20)
The Buddha said, “Have a toothless cow eat husked wheat. Later it will then eject the grain still whole. Use this for roasted flour and take it when it is untimely.”
Untimely here refers to the time between midday and dawn when a Buddhist monk or nun is not to normally eat anything. Here the roasted flour is probably something akin to Tibetan tsampa, which is roasted barley flour that is made into something like porridge with butter tea and still consumed by Himalayan people today.
It might seem odd to most modern people that garlic could be considered so offensive, yet cow dung was seen as pure. Again, this is a large cultural difference and demonstrates how subjective the “purity” of substances can be across the cultural spectrum of humanity. We might think garlic as generally agreeable (at least in cuisine) while thinking cow manure rather repulsive. In the Buddha's time it seems to have been the complete opposite. Cow dung is one of the “five pure products” (pañca-gavya) of a cow which include urine, dung, milk, cream and butter.
Incidentally, in present day India you can still see plenty of people in the countryside making discs of dried cow dung with which they heat their homes and cook their food (as seen here on the banks of the Ganges River in Varanasi in a photo I took). As I was informed when I visited the ruins, even the kitchens of the great Nālandā University in ancient times were fired with dried cow dung. It is quite a versatile substance, though I hear burning it is bad for the eyes and causes vision disorders after extended periods of time.
To dispel any doubts that this rule against garlic was limited to just one sect, we should note that the Mahāsāṃghika Vinaya prescribes a nearly identical protocol for one taking garlic medicinally. This text is thought by some scholars to be the most ancient vinaya rendition available to us, which at the very least in this context would suggest that there truly was a garlic prohibition in the early sangha and that this was not a later development.
《摩訶僧祇律》卷31：「服已應七日行隨順法。在一邊小房中。不得臥僧床褥。不得上僧大小便處行。不得在僧洗脚處洗脚。不得入溫室講堂食屋。不得受僧次差會。不得入僧中食及禪坊。不得入說法布薩僧中。若比丘集處一切不得往。不應遶塔。若塔在露地者。得下風遙禮。七日行隨順法已。至八日。澡浴浣衣熏已得入僧中。」(CBETA, T22, no. 1425, p. 483, b29-c7)
“When the treatment is completed, for seven days one will abide by [the following] rule. Be in a small periphery room [of the monastery]. One must not lay on the sangha mattress. One must not use the sangha lavatory. One must not wash one's feet in the sangha feet washing area. One must not enter the bathroom, lecture hall and dining hall. One must not [attend] offering gatherings based on seniority. One must not enter in among the sangha when eating and the meditation hall. One must not enter in among the monks when the Dharma is being taught or precepts are being recited. If the bhikṣus assemble together in one place together, one must not go. One should not circumambulate stūpas. If a stūpa is on open ground, one must do prostrations downwind far from it. Having followed the rule for seven days on the eighth day one bathes, washes one's clothes and scents them before being allowed to enter in among the sangha.”
Note here there is no mention of smearing cow dung in the living space to purify it. Clearly the smell of garlic was considered so offensive that such measures were deemed necessary. It begs the question if the Buddha actually prescribed such protocols. While it does seem that the Buddha laid down a rule against eating garlic, the additional material as quoted above found in the vinaya literature is perhaps from a later period given the mention of stūpas and caityas. In any case, this led to the ongoing prohibition on garlic consumption in later times in realms outside India where sensitivities were different.
In the west I suspect a lot of Buddhists are apathetic when it comes to dietary restrictions beyond vegetarianism, which is seen favorably but is by no means universal. Not many people are aware that garlic was strictly forbidden in the early sangha, let alone onions, leeks, shallots, and even brewer's yeast and lees (the leftover grain after brewing alcohol). The latter two are described as capable of intoxicating people, thus they were forbidden. However, these dietary restrictions apply to formally ordained renunciates as per the vinaya (monks and nuns), so it is not really relevant given that in the western world there are so few bhikṣuṇīs and bhikṣus, though this could change in time. One issue I see though is that dietary considerations and formal protocols as outlined above are generally seen as secondary, even unimportant, in spiritual practice, hence why it is unlikely to be given any consideration.
Then again we can't expect someone to go into solitary retreat for a week because they ate some garlic and then cleanse their room with smeared cow dung. The Buddha actually provided a caveat in this respect as recorded in the vinaya of the Mahīśāsaka school:
《彌沙塞部和醯五分律》卷22：「雖是我所制。而於餘方不以為清淨者。皆不應用。雖非我所制。而於餘方必應行者。皆不得不行。」(CBETA, T22, no. 1421, p. 153, a14-17)
“Even if it be something I have prohibited, if it is not considered pure [conduct] in other lands, then it all should not be adopted. Even if it is not something I have prohibited, if something must be carried out in other lands, then it all must be carried out.”