奧古斯丁雙城說的思想溯源探析

在《上帝之城》卷11－22中，奧古斯丁詳細闡述了上帝之城與地上之城的構想，包括雙城的起源、發展和終局。奧古斯丁從未表明雙城說是他的獨特發明，但他也沒有明確指出他的引用來源。在本文中，我們從以下三組關鍵詞追溯奧古斯丁雙城說的思想淵源：二元與非二元、相繼與並存、混雜與純粹：無論在善惡實體二分上還是肉身與精神二分上，奧古斯丁的雙城都不是嚴格的二元論，而是一元上帝之下兩種截然對立的生活取向與生活目的；上帝之城的已然與未然使得奧古斯丁的雙城兼有相繼與並存兩個方面；奧古斯丁突破了以耶路撒冷和巴比倫作為雙城代表的絕對劃分，並發展了保羅有關「靈性和肉體的以色列人」，使每一個個體都有了雙城的雙重身分，這些使得奧古斯丁的雙城兼有純粹與混雜的雙重特點。這三組關鍵詞既體現了奧古斯丁雙城說的複雜之處，也精煉地展現奧古斯丁雙城說的核心要素，以這三組關鍵詞為線索，我們可以看到「上帝之城」和「地上之城」的用法雖非奧古斯丁的獨創，兩城的對立以及前者的公民寄居於後者的思想早已存在於奧古斯丁之前的古代思想（包括基督教與非基督教）中，奧古斯丁的雙城說固然是集古代各種雙城思想的結晶，但遠比既有的雙城說複雜許多，也原創許多。比起同時代教會人士對羅馬傾覆的種種回應，奧古斯丁的雙城說無疑給當時的信徒帶來最徹底的提醒與慰藉：塵世的一切都在至善上帝的掌控之下，羅馬的傾覆並不是邪惡力量使然；羅馬帝國作為塵世文明的一部分，其善好是低階的，其壽數是有限的，信徒作為上帝之城的公民，不過是地上之城的寄居者，其生活與福祉應追求上帝之城的愛與和平，後者終必全然實現；雙城在塵世是混雜的，信徒所組成的社群應保持純粹和可辨識性，在塵世中踐行上帝的律。

關鍵字

奧古斯丁；《上帝之城》；雙城說；溯源；羅馬陷落

並列摘要

In the book 11-22 of De civitate Dei, Augustine elaborated the vision of a heavenly city and an earthly city, including their origins, developments and endings. Neither did Augustine describe this idea as his original invention, nor did he point out his source. This article traces the source of Augustine's two cities from three groups of keywords: dualism/non-dualism, overlapping/succession and mixture/purity. These three groups of keywords highlight key themes as well as the complexity of Augustine's idea. Based on this comprehensive understanding of the two cities, it is hard to equate Augustine's two cities to any antecedent established thought. Augustine's idea of two cities is the quintessence of certain ancient philosophies, but is much more complex than them. Compared with his contemporaries, Augustine's idea of two cities brings out thorough reminder and comfort: all in this world is under the sovereign of God, therefore the fall of Rome is not the triumph of evil power; the goodness of Roman Empire, a part of secular civilization, is secondary and limited while the believers, who are only pilgrims in the earthly city, shall pursue the love and peace of the heavenly city, which will realize fully in the end; although the two cities intermingle in the secular time, the community of believers practice the law of God and keep pure.