大般涅槃經義記 7.221

7.221

下明大中，先喻後合。下以淨義顯涅槃大，「淨故名大」總以標舉，下別顯之，先問舉數，「何等四」下問以辯相。初一果淨、第二因淨，此二斷德；第三身淨、第四心淨，此二行德。如《地持》中亦說四淨：一者身淨、二者心淨、三境界淨、四者智淨。彼身與心與此相似，境淨、智淨與此不同，法門差別，不可一等。

Below, in clarifying greatness, first is the metaphor and afterward the application. Below, through the meaning of purity, it reveals the greatness of nirvāṇa; "because it is pure it is called great" generally marks it out; below it reveals it in detail: it first asks and raises the number; from "what are the four?" downward asks to analyze the characteristics. The first is fruit purity, the second is cause purity; these two are virtues of abandonment. The third is body purity, the fourth is mind purity; these two are virtues of practice. As in the Bodhisattvabhūmi, it also speaks of four purities: 1. body purity, 2. mind purity, 3. object purity, 4. knowledge purity. Its body and mind are similar to this; object purity and knowledge purity differ from this: because of the differences in dharma-gates, they cannot be made uniform.