佛遺教經論疏節要 1.414

1.414

First, this is revealed by a simile. The moon is the essence of extreme yin and is therefore cold; the sun is the essence of extreme yang and is therefore hot. That their natures cannot be altered is known to everyone in the world. Now saying that they could be made hot or cold means that even if the sun and moon were to alter their natures, the Buddha's words would never change. 'Cannot be made into pleasure' means that suffering and pleasure are each real and do not change. 'There is no other cause' means that the cause of origin definitely brings about the fruit of suffering, and is never brought about by the causes belonging to the path. The treatise says: 'Because it indicates that the extinction of suffering has its respective cause.' 'It is because its cause is extinguished' means severing the cause of origin. Furthermore, the extinction of the cause is sopadhiśeṣa-nirvāṇa. 'Because the cause is extinguished, the fruit is extinguished' means that future existence does not arise from within the cause, which is the extinction of the fruit of suffering. Furthermore, the extinction of the fruit is nirupadhiśeṣa-nirvāṇa. 'There is no other path' means that other paths are not true and cannot lead to extinction.