Heart and mind are of primary importance in Buddhism and the “Lankavatara Sutra” proclaims that “all worldly phenomena are illusory” and presents us an in-depth exposition elucidating the principles of the Tathagatagarbha. In this sutra, the Buddha expounds the Dharma to Ravana, the demon king of the Lanka City, and other demons. Buddha’s elucidated directives call for total abstinence from all meat-eating and enumerate the depravities of meat-eating. Towards the end of the sutra one begins to understand why the Buddha proclaimed the strict prohibition of killing and any kind of meat eating to the demons of the Lanka City. One can also see why the “Lankavatara Sutra” provides one full chapter exclusively on “restraining meat-eating” ( the Prohibition of all kinds of meat eating ) which firmly repudiates the many variant rules based on expedience adopted by some other sutras and by the Abhidharmas of some sectarian branches. In the “Lankavatara Sutra”, Buddha is repeatedly giving us guidance with respect to the consumption of meat. In Buddhist sutras, Yaksha the demon also frequently appears everywhere in our mundane world. Yaksha is the demon and one of eight groups of spiritual beings . Also, Yaksha’s existence is known, yet it remains a mysterious demon. Thus, my interest in Yaksha was aroused. I am striving to find the answer by exploring its origin from the ancient myths in India, and sorting out the important relevant records in Buddhist literature. With regards to vegetarianism in Buddhism and the so-called “three clean meats”, contemporary opinions on these issues are in fact disorderly and numerous. Communities of Buddhist monks in the Northern Buddhism (Mahāyāna；Great Vehicle Buddhism) and those in the Southern Buddhism (Hīnayāna；Lesser Vehicle Buddhism) each have their own opinions on the consequences of eating meat in reference to the Moral Disciplines of Buddhism. As of today, a consensus has not been reached. It is the intention of this research to find out how imperative it is for a Buddhist monk to become non-attached to the taste of meat, and maintain a vegetarian menu in order for him to be genuinely steadfast in the divine aspiration of non-cruelty, and, furthermore, to examine whether those alleged “three clean meats” are really fit for consumption by monks in the holiness of a Buddhist monastery. Buddhist monks in China of the Northern Buddhism (Mahāyāna) denomination have successfully maintained steadfast and unwavering in vegetarianism throughout history even till today in accordance with the spirit of scriptural references. Through millennia of tradition, and centuries of affirmation, not the slightest trace of regret or dissatisfaction has ever come up in the communities of Mahayana Buddhist monks regarding vegetarianism, they must have been drawing transcendent delights and inspiration from vegetarianism. These subjects are also within the main scope of discussions in this treatise. This research starts with both extensive retrieval and critical investigation of evidence from the earliest Buddhist Sutra, namely The Āgama Sūtras , to ascertain the diet of the original Buddha’s Sanga. It continues with discussion of the sutras of The Mahāparinirvāṇa Sūtra , Aṅgulimālika Sūtra , Mahāmegha Sūtra and Śūraṃgama Sūtra. In Buddhism since the starting
