“Having dispelled the thoughts and purified one’s channels, energies, and essence, when one rests without wavering in the empty nature of the mind, three different experiences may occur: experiences of bliss, clarity, or voidness, which correspond to the nirmanakaya, sambhogakaya, and dharmakaya, respectively. However, if these experiences are tinged with clinging, the bliss will lead to rebirth in the world of desire; the clarity, to rebirth in the world of form; and the absence of thought, to rebirth in the world of formlessness. So while these three experiences will, and indeed must, occur as a normal result of progress on the path, when they occur, you must not have the slightest clinging to them but permeate them with the realization that they are completely empty. Realize that they are simply manifestations of your own mind. Even if you reach a stage where you are able to stay in unwavering concentration for days and days without even feeling hungry or thirsty, you must never feel proud or pleased with yourself. Stay free of clinging and pride, pray with fervent devotion to the teacher, and practice diligently. That way, you will easily develop these various kinds of concentration. As it is said, everything can be accomplished with a little hardship. But if one remains idle and indifferent, it is difficult to achieve anything. So in order to cultivate these experiences of bliss, clarity, and voidness you should bring everything into one-pointed concentration.”
~ Kyabje Dilgo Khyentse Rinpoche
“Zurchungpa’s Testament : A Commentary on Zurchung Sherab Trakpa’s Eighty Pieces of Advice”