Religious Zen VS. Pure Zen
There is a distinction between ‘Religious Zen’ and ‘Pure Zen’.
Religious Zen, is that of the Mahayana canon and speaks to the Bodhisattva path of Buddhahood. The Zen of Japan is certainly towards this view, however, the Ch’an of the old Zen masters tends to be on Pure Zen.
Pure Zen, is the absolute nature of Zen without the religious overtones and aspirations.
There is no Zen Bible, never was and never will be. There is the Mahayana Canon, that are a loose collection of writings speaking to the Bodhisattva Path, however, there is no specific practice called Zen in them.
One can know Pure Zen without embracing the Bodhisattva path, the Bodhisattva Path can be embraced without knowing Zen at all.
Zen Buddhism is the marriage of the Zen insight and the Bodhisattva Path, in creating a religious view and aspiration, and becomes its own thing. Those that reside in Pure Zen in where wisdom and knowledge flow, need not at all be a disciple of the Buddha or the Mahayana.
You may be correct in that. Back in the 80’s we called ourselves Mahayanist, not Zen students when I was a member of the Zen Dharma Centers. To claim Zen as a Mahayana creation, as in owning it, would be a similar claim as to like to claim that “Christians’ own prayer”, and that is a demonstrably false claim.
To make it clear, there are Mahayanist traditions well outside of the Japanese Zen lineages; Tibetans come to mind, Pureland of course, and so many others!
Yet, it does seem that today there is a lot of confusion in the Zen Centers as to what exactly is being taught and a lot of blurring the lines as to what is Zen and what is Mahayana.
Zen is not a religion, never will be. Mahayana is a religion but is not Zen. There are a lot of really bad teachers in the dharma centers who simply do not understand this, and they have no clue – mostly because they are very under-read, and have no clear insight or understanding of Zen or Mahayana. Unfortunately, many newbie students encounter these teachers and get filled with all kinds of false notions about Zen that are just not so!