大般涅槃經義記 1.30

1.30

'In the land of Kuśinagara' and so forth is the place of conversion. The places are distinguished into four: first, the country; second, the ground; third, the river; fourth, the grove. Wandering and teaching within the place, it is designated as 'being in.' The land of Kuśinagara is named after the city; here translated, it is called 'Soft Grass'; in the Āgamas it is called the 'City of Kuśa Grass.' The Malla ground distinguishes the place in terms of its people: the country's borders are broad and expansive, and so it is further designated specifically; the various sons of the Mallas were born in this place, hence it is called the birthplace of the Mallas. Beside the Hiraṇyavatī River distinguishes the place in terms of the river: the birthplace is still broad, and so it is further discerned; translated in this region, it is named the Golden Sand River. The Sāla trees distinguish the place in terms of the grove: the river is still broad and long, and so it is further specifically designated; translated in this region, it is named the Indestructible Grove; remaining unchanged in winter and summer, it is called the Indestructible Grove. Why is it in these two places—this country and these trees? The text below will explain of itself; regarding the two places of the ground and the river, there must also be reasons, but since the text does not discern them, one should not speak rashly. Someone here used phenomenal events to express the Dharma, saying that the city of Kuśi is the city of immortals, and immortals have long life, symbolizing the Buddha's long life. The birthplace of the Mallas symbolizes the Buddha's great power, which cannot be subdued by the four māras. The Golden Sand River symbolizes that the river of nirvāṇa possesses the sands of buddha-nature. The Indestructible Grove symbolizes that the Tathāgata's true body is firm and indestructible. It may well be like this, but since it is not spoken by the sūtra, it cannot yet be taken as definitive.