本文從服飾思想與視覺論述的角度，重新理解英格蘭教會於1550年代及1560年代所發生的兩次祭衣之爭，其主要關懷有二：一，祭衣之爭中服飾是在何種思想脈絡下被討論，又被賦予何種宗教意義？二，祭衣作為一類特殊的服飾，它在視覺上傳遞的訊息，以及它所引發的焦慮是什麼？本文第一節簡要介紹宗教改革時期路德派與英格蘭教會所發生的祭衣之爭，以及祭衣問題的重要性。第二節討論當時與祭衣最為相關的宗教概念，即「中性之事」（adiaphoria, things indifferent），或可譯為「無關救贖之事」。「中性之事」的討論，在宗教改革時期以日耳曼地區的路德派最為興盛，瑞士地區的茲文利派與克爾文派也間或談及，因此本文第二節的內容以路德派對中性之事的討論為主，第三節及其後討論到英格蘭祭衣之爭中的辯論時，則會提及茲文利派或克爾文派的意見，如此讀者一方面可瞭解 此概念在歐陸宗教改革中的重要性，也可看見英格蘭宗教問題與歐陸各教派之間的連結關係。第三節至第五節，由於本文篇幅所限，將以愛德華時期的祭衣之爭為主，並以「祭衣」為主體，從三個不同的脈絡瞭解祭衣之爭的性質：一、宗教思想的脈絡，其關心的問題在於祭衣是否可視為中性之事、中性之事又如何界定？二、政治權威的脈絡，其主題是中性之事由誰管理與規範？祭衣若是中性之事，誰可決定穿戴與否？三、視覺文化的脈絡，由中古至宗教改革時期對「視覺」問題的思考出發，討論祭衣所引發的視覺效應，以及它在視覺上所造成的形象區隔。本文藉此三個脈絡指出，祭衣之爭不但是一場有關宗教與政治的衝突，也是一場視覺論戰，攸關教會信仰與形象的定位；同時它也幫助我們了解宗教改革運動中「無關救贖」的那一面。

This article revisits the vestments controversy in sixteenth-century England with a new emphasis on clothing and visual discourses. Two concerns dominate this research: first, how the function and meanings of vestments were contemplated in Reformation Europe? Second, what was the message expressed when a priest was seen in this particular form of dress, and any anxiety arose from that? The first section of this article briefly introduces the vestments controversies occurred in the Lutheran Church in the mid-1520s, and in the Church of England in the 1550s and 1560s. Then, in the second section, it moves to discuss the concept of adiaphora, or things indifferent, where the issue of vestments was usually situated during the Reformation. Begun with Erasmus, the concept of adiaphora was borrowed from ancient philosophy and appropriated into Christianity to mean things 'neither commanded nor forbidden by Scripture', or 'non-essential things', which were not necessary for salvation. However, there were acrid debates on the definition and regulation of things indifferent during the Reformation, especially in the Lutherans. English controversy of the vestments was actually an extension of the continental adiaphoristic controversy and there were also several continental reformers participating in the English controversy which, however, focused primarily on the religious apparel. The following three sections therefore investigate the English vestiarian controversy of 1550-51 around the concept of adiaphora, and its involvement in three connected dimensions: religious, political, and visual. For the religious, the third section shows the debate on whether the vestments were a matter of indifference or not among the polemists in the reign of Edward VI. For the political, the fourth section examines the issue concerning to which the authority of governing and regulating vestments belonged, the individual, the church, or the government. For the visual, the sixth section explains the theoretical change of religious visuality from the medieval church to the Reformation, and then concentrates on the visual benefit or anxiety, and the church images, created by the sartorial distinction between clergy and laymen. In conclusion, English vestiarian controversy was not only a debate on religious ideas and political authority, but also a visual battle for the image of the church and clergy. It serves as a lens to see the essential part of the Reformation by its 'non-essential' matters.