He is one of the principal people who have promoted the idea that the ancient Maya calendar ends on 21 December 2012 and this portends major changes for the Earth. He has self-published a number of books through his Four Ahau Press. Jenkins considers scientific approaches to cosmology a byproduct of limited thinking.
In Tzolkin: Visionary Perspectives and Calendar Studies, he writes, "I primarily wish to promote a visionary approach to these matters, as there is much more to the Sacred Calendar than can be seen with the rational intellect," and that these visionary perspectives "can more closely touch the spirit of the calendar" than does the anthropological literature.
He claims that a higher state of consciousness and universal understanding exists, and that it is subconsciously present in modern humans through a primordial memory, but that these higher planes of thought were more easily accessible to humans of the remote past, such as the ancient Mayans
Jenkins accounts for this access in Maya Cosmogenesis 2012: "From studies in iconography and ethnobotany, we know the ancient Maya radically altered their perceptions in order to have visions of the underlying nature of reality. Jenkins also maintained that, in order to accept and understand his cosmological theories, one must also accept the premise that the Mayan kings journeyed to “distant places,” and continuously “renewed” their kingdoms at specific points in the Mayan calendar.
Jenkins is also a supporter of “The Lost Star” theory which extrapolates the existence of a binary companion of the Earth’s sun based on a believed mathematical discrepancies in “earth wobble.”
In October of the year 2000, Jenkins work was featured on two episodes of Places of Mystery series on the Discovery Channel. Jenkins was interviewed and appears in the film Manifesting the Mind a film by Andrew Rutajit, executive producer of Bouncing Bear Films.
Jenkins is featured speaking in the documentary 2012: Science or Superstition.
The film explores the interpretations of the ancient Mayans predictions by researchers and scholars. Jenkins is also featured in the documentary/film 2012: Startling New Secrets.