He is best known for his collaboration with Helen Schucman in typing the original manuscript and being on the editing team for A Course in Miracles (ACIM), a self-study curriculum in spiritual psychology.
[1] He died in 1988, aged 65, in Tiburon, California, after having made his involvement with the ACIM material and its study the most central focus of his life.
At the age of seven, the untimely death of his older sister caused his parents to disavow their affiliation with the Church of Christian Science.
After graduating from DePauw in January 1944 until the summer of 1945, Thetford had a job as an administrative officer at the University of Chicago working with the scientific team doing atomic research.
A C.V. listing his positions, affiliations, grants, publications and papers is given as Appendix 2[3] in a biography Never Forget to Laugh by Carol Howe.
[4] The funded social science research projects produced knowledge that was quietly harvested by CIA personnel[5][4] to develop persuasion, interrogation and torture methods.
[4] For example, in 1961, Thetford was researcher in Subproject 130[6] that explored[7] the relationship between personality dimensions and clinical symptoms using the Wechsler intelligence scales.
The working relationship between Thetford and Schucman was apparently often somewhat strained, yet throughout these difficulties they would always maintain a certain level of professional courtesy and respect for one another.
Soon they recognized that the notes, which eventually became A Course in Miracles (referred to as The Course by ACIM students), was their answer, the "other way" that they had agreed to find together four months earlier.
During the process Schucman claimed to have the mental equivalent of a tape recorder in her thoughts, which she described as being able to turn on and off at will, at her convenience, so that she might be able to transcribe into shorthand notes, what she was internally hearing.
Thetford, Wapnick and Schucman, the three principle transcriber-editors of ACIM were to remain friends for the rest of their lives, throughout the arduous process of seeing this manuscript through to first successful publication, and beyond to witness the initial spreading of its teachings.
Now in Tiburon at age 57, Thetford transitioned into a sort of semi-retirement, no longer accepting any demanding positions of heavy responsibility in either his professional life or in his involvement with the ever growing readership of ACIM.
In California, Thetford took on two part-time professional positions; one as a psychology consultant at Travis Air Force Base and the other as one of the directors of the ACIM-related Center for Attitudinal Healing in Tiburon, as offered to him by his friend and fellow student of ACIM, Gerald Jampolsky.
Instead, during this final period of his life, he appears to have been primarily concerned with his own personal study of the ACIM material, and with enriching his own grasp of its message.