Twitchell was one of the greatest plagiarists of this (or any other) century, and much of what he "wrote" was actually material he blatantly copied word for word from the published works of legitimate authors. One of his more popular early books was The Far Country, which alone carried over 400 solidly-documented stolen paragraphs, complete with typos and syntax errors. His other books all follow in the same pattern. He claims these ancient and most secret teachings were taught to him by a 500 year old Tibetan lama named Rebezar Tarzs, who would appear to him in his apartment each night and dictate the truths. The real truth is that he found his material at the local public library, in the metaphysical section.
His most important book, The Tiger's Fang, was a purported journey he took deep into the inner planes, escorted by Rebezar Tarzs, and was taken to meet God directly. Alas, like the rest of his works, much plagiarized material is to be found in this book, (Walter Russell's "The Secret of Light", as an example), as well as the standard cosmologies taught by Sant Mat and Radhasoami. There's serious doubt about his credibility, with so many stolen passages being claimed as his own experiences, when, in fact, they were the experiences of other authors.
It's quite clear the real sources for his "secret" teachings were the published works of authors like Julian Johnson, Neville, L. Ron Hubbard, Lama Govinda, Walter Russell, Swami Premananda, Kirpal Singh, Annie Besant and many others. He worked for the notorious L. Ron Hubbard for a period of time in the 1950s and was instrumental in recruiting people into that questionable organization. What he learned in Scientology, he freely applied to his own invention Eckankar.
His official biography, In My Soul I Am Free, was written by Brad Steiger (the UFO chaser) and was sold by Eckankar for over 30 years and has been found to be an almost complete fabrication. Professor David Lane stripped away the facade of Eckankar with his writings and also interviewed scores of people who had known Twitchell. It was just about unanimous that Twitchell was a compulsive liar since childhood and is a highly unreliable source.
With so much evidence that Twitchell was a world-class liar, this presents the student of Eckankar with an uncomfortable issue to struggle with. If a teacher can't be trusted to tell the simple truths of his own life, what makes a student think he's telling the truth about the inner worlds of Spirit? Would you buy a used car from this man?