「捨念清淨」(upekkha-sati-parisuddhi)一語，是表達佛教禪那境界中第四禪內容的關鍵用語。但這個用語的意義所指為何，至今仍異說紛紜，無有定論。本文的目的，即在嘗試解決此一問題。

本文首先考察當前學界（包括歐美緬日的種種翻譯及研究）對此語的理解，以及古代論書（包括巴利系及說一切有部為主的諸論書）對此語的解釋，並將各種解讀歸納分類，指出其特徵及引起爭議的關鍵所在。

接著，本文回到契經——阿含經和尼柯耶文本，重新考察此語在早期佛教禪修脈絡中的實際意義。考察結果顯示，「捨念清淨」一語比較適切的讀法應是「具捨與念，心極清淨」，也就是，捨、念、清淨三詞，皆為描述第四禪禪心的狀態。這個讀法和當前學界及古來論書的解讀都不相同。

基於上述研究，本文最後指出在早期佛教研究中，文獻運用上的一些問題。

The phrase upekkha-sati-parisuddhi (equanimity-mindfulnesspurification)
commonly occurs in the Pali Canon as part of the stock description of the fourth jhana in Buddhist meditation, yet there is still no consensus amongst Buddhist scholars as to its interpretation. This article is an attempt to solve this problem.

I start by examining the various interpretations provided by contemporary scholars from both the East and the West, and then proceed to discuss how the term has been interpreted by the ancient commentators, especially those of the Theravada and Sarvastivada traditions. Then, after summing up and categorizing the various interpretations, I examine their respective characteristics and controversial points.

I then examine the related passages in the Nikayas and Agamas, taking a fresh look at the actual meanings this phrase had in the meditation traditions of early Buddhism. Based on this I conclude that the most appropriate interpretation of upekkha-sati-parisuddhi is “a state of equanimity, mindfulness and purification (of mind).” Thus I take all three terms to be a description of the concentrated mental state of the fourth jhana, although this way of reading the phase is a variance with all of the contemporary and ancient interpretations.

As a follow-up to the research described above, I conclude the paper by examining some issues relating to the use of literatures in studies of early Buddhism.