Learned audience, when you hear me talk about the void, do not at once fall into the idea of vacuity [because this involves the heresy of the doctrine of annihilation]. It is of the utmost importance that we should not fall into this idea, because when a man sits quietly and keeps his mind blank he will abide in the state of voidness of indifference.
Learned Audience, the illimitable void of the universe is capable of holding myriads of things of various shapes and forms, such as the sun, the moon, stars, mountains, rivers, worlds, springs, rivulets, bushes, woods, good men, bad men, dharma pertaining to goodness or badness, deva planes, great oceans, and all the mountains of Mahameru. Space takes in all of these, and so does the voidness of our nature. We say that the essence of mind is great because it embraces all things, since all things are within our nature. When we see the goodness for the badness of other people we are not attracted by it, no repelled by it, nor attached to it; so that is our attitude of mind is as void of space. In this way, we say the mind is great. Therefore we call it Maha.
Learned audience, what the ignorant merely talk about, wise men put into actual practice with their minds. There is also a class of foolish people who sit quietly and try to keep their minds blank. They refrain from thinking of anything and call themselves great. On account of their heretical view we can hardly talk to them.
(The Diamond Sutra & Sutra of Hui-Neng,
Chap. 2, On Prajña, p. 80, translated by A.F. Price & Wong Mou-lam).