That's a good question, Astus.
Here's the usual response I get back in reply when I ask one particular "mikkyo" group just what they teach:
In this tradition we study the teaching of Buddha, but also Jesus, Krishna and Melkitzdeck. We observe and grow through experiences.
Comportments such as anger, arrogance, jalousie and hatred are at the origins of suffering. These comportments and the suffering that comes out of them are caused by the lack of consciousness of the
people. People are imprisoned in this suffering and search for a way to make it through. This suffering is majorly caused by the person herself. It is by looking at ourselves, by observing our ego’s mask and by awakening our consciousness that we
can eradicate these false conceptions, true root of suffering. These false conceptions come from the attachment to material goods, to relationship and to the value we give to our own identity.
These attachments are the true roots of suffering. It is by finding their source, their roots, that we can grasp, understand its nature, and finally free ourselves from it.
This is the thought and attitude that constitute the foundation of Mahajrya Buddhism.
Here is another version of the same, from an exchange of email with a different representative:
Well, naturally we are learning to be happy and realize ourselves, by dissolving the concepts of possession, relationship and identity
We look to five spiritual masters for our wisdom. The first is Buddha, for the consciousness of compassion. The second, Krishna, from whom we learn to live in non-action. Non-action does not mean non acting, it means acting responsibly but not being attached to the outcome of our actions. The third is Jesus, for the consciousness of charity and forgiveness. The fourth is Melkezedek, for Divine Justice. This means that we strive to stop competing with others in any way--there is no concept of human fairness here, everything that happens we bring to ourselves to further our own spiritual evolution (he's also the father of Kabbalah, and this is taught to those who want to learn it). The fourth is MahaVajra, our current spiritual master who is a reincarnation of the MahaVajra who lived several thousand years ago. He teaches expedient means and how to efficiently purify the ego with a technique called emotional integration.
We embody this wisdom by studying processes such as Kuji-in, Kama Chakra, the Elements of Creation, Atma Yoga, Kundalini Yoga, Healing, NagaRaja process, the Siddha path, Immortality process, Quantum Metaphysics, Kabbalah, and more.
I'm not sure how this can be characterized within the context of Mahayana Buddhism, much less Tendai specifically.
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