What is the "meditation on emptiness" in MN 121?
What does "emptiness" refer to in this sutta?
Also, what does "oneness dependent on the perception of ..." mean in this sutta?
“Indeed, Ānanda, you properly heard, learned, attended, and remembered that. Now, as before, I usually practice the meditation on emptiness.
Consider this stilt longhouse of Migāra’s mother. It’s empty of elephants, cows, horses, and mares; of gold and money; and of gatherings of men and women. There is only this that is not emptiness, namely, the oneness dependent on the mendicant Saṅgha. In the same way, a mendicant—ignoring the perception of the village and the perception of people—focuses on the oneness dependent on the perception of wilderness. Their mind becomes eager, confident, settled, and decided in that perception of wilderness. They understand: ‘Here there is no stress due to the perception of village or the perception of people. There is only this modicum of stress, namely the oneness dependent on the perception of wilderness.’ They understand: ‘This field of perception is empty of the perception of the village. It is empty of the perception of people. There is only this that is not emptiness, namely the oneness dependent on the perception of wilderness.’ And so they regard it as empty of what is not there, but as to what remains they understand that it is present. That’s how emptiness is born in them—genuine, undistorted, and pure.
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Whatever ascetics and brahmins enter and remain in the pure, ultimate, supreme emptiness—whether in the past, future, or present—all of them enter and remain in this same pure, ultimate, supreme emptiness. So, Ānanda, you should train like this: ‘We will enter and remain in the pure, ultimate, supreme emptiness.’ That’s how you should train.”