Keizan Jokin (1268-1325)

The author of Denkoroku, a master in the fourth generation of Dogen’s lineage, explains: “Comprehend thoroughly, investigate and penetrate completely, and you will know there is a body that has no skin, flesh, bones, or marrow.  This body cannot be shed even if one tries to shed it; it cannot be abandoned even if one tries to abandon it.  Therefore this realm is referred to by the expression, ‘when all is exhausted, there is a place that cannot be emptied.’  If you can understand thoroughly, you won’t doubt what the Zen masters and Buddhas say.  What is the principle?  Clear as pure light, no inside or outside—is there any body or mind to be shed?”

From Introduction to Dogen Zenji Goroku (Sayings of Zen Master Dogen). Thomas Cleary.