The Vajra Prajna Paramita Sutra, p168-169After having spoken the previous section of text, Śākyamuni Buddha realized people might have doubts and become attached to the mark of the Tathagata’s comings and goings. Therefore he said to Subhūti, “If someone were to say the Tathagata either comes or goes, either sits or lies down, that person would not understand the meaning of my teaching.” It seems as if the Tathagata, the Thus Come One, comes and goes but the coming and going is only illusory. Anyone who thinks he really comes or goes has failed to understand the principle the Buddha teaches. The Tathagata has no place from which he comes and no place to which he goes; therefore he is called the Thus Come One. That means the Buddha’s dharma body neither dwells nor does not dwell. It pervades all places. If it fills all places, from where could it come? Since it fills all places, to what place could it go? Therefore it is said not to dwell and not not to dwell.
If you understand the Buddhadharma, the mountains, rivers and great earth are all the Tathagata’s dharma body. If you do not understand, you see the Tathagata but do not recognize him. If you understand the Buddhadharma, you can recognize the Buddha without even having seen him, and once you recognize the Tathagata, it is very easy to rely on the dharma to cultivate. If you don’t recognize the Tathagata and do not even know what the Buddha is all about, how can you study the Buddha? To fail to recognize yet to proceed to study is called the blind leading the blind. If you are blind you may make a mistake and choose to follow someone who is also blind. Although your leader realizes that he himself is blind, he may want to be followed and so pretends he can see. The two of you then fumble along, running hither and yon, until eventually you both fall into the sea and are drowned. It is essential from the start to recognize the Buddhadharma and to understand how to cultivate. Then you can study.