Everything Shown in Brahmā's Palace
Two last similes for the eighth concentration. A dragon lives on the ground and his weather fills the sky — and the palaces people think they see up there are a mirage. Then a Brahmā palace in which an entire world-system appears, down to the specks of dust floating in the air.
The Dragon Below, the Cloud Above
The simile has a correction built into it: what you take for a palace in the sky is not one, and the real dwelling is on the ground under your feet.
佛子！譬如龍宮依地而立，不依虛空，龍依宮住，亦不在空，而能興雲遍滿空中；有人仰視所見宮殿，當知皆是乾闥婆城，非是龍宮。佛子！龍雖處下而雲布上。菩薩摩訶薩住此三昧亦復如是，於無相入有相起，於有相入無相起。
Child of the Buddha! It is like a nāga palace, which stands upon the ground and does not rest on open space; and the nāga dwells in his palace and is likewise not in the sky, and yet he can raise clouds that fill the whole sky. If someone looks up and sees palaces there, know that they are all gandharva cities and not the nāga's palace. Child of the Buddha! Though the nāga is below, his clouds spread above. A bodhisattva mahāsattva abiding in this samādhi is likewise — entering in the characteristicless they rise with characteristics, and entering with characteristics they rise in the characteristicless.
當知皆是乾闥婆城 — know that they are all gandharva cities. The 乾闥婆城 is the standard Indian term for a mirage — a city seen shimmering above the horizon. The simile is not only about high and low; it warns that the impressive thing overhead is the illusion, and the working dwelling is unremarkable and on the ground.
The Palace That Shows Everything
A single room in which a whole trichiliocosm is visible — the heavens, the hells, the mountains, the rivers, the villages, and the motes drifting in the air.
佛子！譬如妙光大梵天王所住之宮，名：一切世間最勝清淨藏；此大宮中，普見三千大千世界諸四天下天宮、龍宮、夜叉宮、乾闥婆宮、阿脩羅宮、迦樓羅宮、緊那羅宮、摩睺羅伽宮；人間住處及三惡道、須彌山等，種種諸山、大海、江河、陂澤、泉源、城邑、聚落、樹林、眾寶，如是一切種種莊嚴，盡大輪圍所有邊際，乃至空中微細遊塵，莫不皆於梵宮顯現，如於明鏡見其面像。
Child of the Buddha! It is like the palace where the great Brahmā king Wondrous Light dwells, named the Most Surpassing Pure Treasury of All Worlds. Within that great palace one sees universally, throughout the four continents of a great trichiliocosm, the palaces of the devas, of the nāgas, of the yakṣas, of the gandharvas, of the asuras, of the garuḍas, of the kiṃnaras and of the mahoragas; the dwelling-places of humans and the three evil destinies; Sumeru and every kind of mountain; the great oceans, the rivers, the marshes and the springs; the cities, the towns and villages, the groves and the many jewels — every such adornment of every kind, out to the farthest limit of the great encircling mountains, and even the fine motes of dust drifting in the air: there is nothing that does not appear within that Brahmā palace, as a face appears in a bright mirror.
菩薩摩訶薩住此一切眾生差別身大三昧，知種種剎，見種種佛，度種種眾，證種種法，成種種行，滿種種解，入種種三昧，起種種神通，得種種智慧，住種種剎那際。佛子！此菩薩摩訶薩到十種神通彼岸。何者為十？所謂：到諸佛盡虛空遍法界神通彼岸，到菩薩究竟無差別自在神通彼岸，到能發起菩薩廣大行願入如來門佛事神通彼岸，到能震動一切世界一切境界悉令清淨神通彼岸，到能自在知一切眾生不思議業果皆如幻化神通彼岸，……
A bodhisattva mahāsattva abiding in this great samādhi of the differentiated bodies of all beings knows lands of every kind, sees buddhas of every kind, liberates multitudes of every kind, realizes dharmas of every kind, accomplishes practices of every kind, fulfils understandings of every kind, enters samādhis of every kind, raises spiritual penetrations of every kind, obtains wisdoms of every kind, and abides in instants of every kind. Child of the Buddha! This bodhisattva mahāsattva reaches ten far shores of spiritual penetration. What are the ten? Namely: the far shore of the buddhas' spiritual penetration that exhausts space and pervades the dharma-realm; the far shore of the bodhisattvas' ultimate, undifferentiated and sovereign spiritual penetration; the far shore of the spiritual penetration that can raise up the bodhisattva's vast practices and vows and enter upon the buddhas' work at the Tathāgata's gate; the far shore of the spiritual penetration that can shake all worlds and every domain and make them all pure; the far shore of the spiritual penetration that can know with sovereign freedom that the inconceivable fruits of all beings' karma are all like a conjuring —
乃至空中微細遊塵，莫不皆於梵宮顯現 — even the fine motes of dust drifting in the air: there is nothing that does not appear within that Brahmā palace. The list has run through heavens, hells, mountains and cities, and then stops at floating dust. What makes the mirror-image telling is not that it holds the large things but that it misses nothing small.
住種種剎那際 — abides in instants of every kind. The ten-fold summary of what this samādhi does ends not with a knowledge or a power but with a way of being in time. Every other item has an object; this one has only a grain.
Part 519 Complete
This continues chapter twenty-seven, 十定品, The Ten Concentrations, in fascicle forty-two. Part 520 completes the ten far shores of spiritual penetration and closes the eighth samādhi; then the ninth begins, sovereign freedom in the dharma-realm, entered in the eye and every sense-field and in each single pore of one's own body.