坐禪三昧經 2.51

2.51

If a practitioner seeking the Buddha path enters dhyāna, he should first fasten his mind and exclusively recollect the physical bodies of all Buddhas of the ten directions and the three times. He must not recollect earth, water, fire, wind, mountains, trees, grass, and plants, any kind of form between heaven and earth, nor any other dharmas at all. He should only recollect the physical bodies of the Buddhas abiding in empty space, like Mount Sumeru, the king of golden mountains, in the midst of the clear water of the great ocean; like a great fire kindled in the darkness of the night; like a banner of the seven precious things in a hall of great giving. The Buddha's body is thus, endowed with the thirty-two marks and eighty minor signs, constantly emitting immeasurable pure radiance. Amid the blue expanse of empty space, he should constantly recollect the marks of the Buddha's body in this way. The practitioner will then attain the samādhi in which the Buddhas of the ten directions and the three times are all before his mind's eye, completely seen. If his mind should take an object elsewhere, he draws it back, making it abide in recollection of the Buddha's body. Then he will see in the east hundreds of thousands of myriad kotis of kinds of immeasurable Buddhas. So too in the south, west, north, the four intermediate directions, above, and below: toward whichever direction he directs his thought, he sees all Buddhas. It is like a person observing constellations at night, seeing hundreds of thousands of immeasurable kinds of stars all at once.