大般涅槃經集解 6.31

6.31

案僧亮曰：此譬廣上事也。城喻涅槃。僧宗曰：佛果排遣累，喻城之防非也。戒防身口外失如墻也，定水為塹也，慧能決斷除惡如俾倪也。保其所得，謂取虛偽物也。寶亮曰：第二奪果也。寶城無體，為眾寶所成。若一德不備，不得稱為大涅槃也。昔之所說，乃是涅槃因緣中說耳。

Sengliang states: "This simile expands upon the matter above. The citadel is an analogy for nirvāṇa." Sengzong states: "The Buddha-fruit dispels defilements, likened to the citadel's defense against wrongs. Precepts guard against external faults of body and speech, like a wall; the water of concentration serves as a moat; wisdom can resolve and eliminate evils, like parapets. Holding fast to what they had attained is called 'taking false and unreal goods.'" Baoliang states: "The second is depriving them of the fruit. The jeweled citadel has no single substance; it is formed of many jewels. If a single virtue is lacking, it cannot be called mahānirvāṇa. What was spoken previously was merely an explanation within the causes and conditions of nirvāṇa."