齋、齋戒一類字詞，早見於先秦文獻；佛教東漸，傳入八關齋法，本土道教也發展出各種齋法。佛道齋法之間的關係，學者眾說紛紜，迄今未有定論。如要疏理和評價，必先對佛道以至中土有關齋一類字詞和概念的意義，作通盤研究；本文專論漢譯佛典，為這研究的第一步。本文比對漢梵巴利語經篇，檢出齋的原語有多個，非如一般論著僅出巴利語uposatha或梵語（u）posadha，進而摘取漢譯佛典有關齋的記述，分門別類作討論，指出佛教之齋，原意謂八關齋，屬俗人的個別修為；由於八關齋的戒規包含由禁殺至過午不食，但只需持守一晝夜，既合乎宗教的聖潔要求，也靈活易行。隨著佛教發展，齋義亦擴展至成為顯密修法，以及提出治病、增壽、求財、求子等各種世俗願求的潔淨準備；持齋的日子初只有三（六）齋日和神變月，後衍生出歲三齋、七日齋，以至日日齋，齋日也成為佛教的特選日子，僧俗各有不同的活動。凡此可見，漢譯佛典之齋義，豐富而複雜。總結部份再辨析八關齋和各種齋目的特色及其印度淵源，期望能為進一步探究中土齋義打下堅實的文獻基礎。

Zhai(purificatory ritual), zhaijie(purificatory observance) and their relevant idioms were first appeared in the pre-Qin Chinese literature. Baguanzhai(eightfold observance) was introduced when Buddhism spread towards China, while local Daoism also developed different types of zhai. Scholars have different opinions on the relationship between Buddhist and Daoist zhai without unanimously conclusion. A comprehensive study of the zhai from different sources should be conducted first before any judgement is made. This article focuses on the Chinese Buddhist translations as the initial step. Firstly, this article compares the Chinese, Pāli and Sanskrit scriptures, and finds out that there are many original terms of zhai, unlike some dictionaries or theses that only suggest uposatha(Pāli) or (u)poṣadha(Sanskrit). Secondly, this article points out that zhai originally denotes baguanzhai which is the personal practice of ordinary people. However, the baguanzhai comprise the precepts from prohibiting killing to not eating after noon, but solely need to obey for a rather short period of time. Therefore, the baguanzhai is not only in line with Buddhist ideal, but also flexible to observe. During the development of Buddhism, the meaning and connotation of zhai gradually became a kind of purificatory preparation for the practice of exoteric and esoteric teachings, as well as many different secular wishes such as good health, longevity, wealth, and offspring etc. Thirdly, baguanzhai was only observed on six days a month and some special observance days at the very beginning. Later, the days of observing extend to include three months a year, seven consecutive days and even on all day. Those days also became significant, and monks and laymen have various activities other than observing zhai. Last but not least, this article analyzes the characteristics of baguanzhai and different types of zhai days and their Indian origins, with an eye to lay a solid literature foundation for exploring the concept of zhai in China.