James was teaching on The Root Verses of the Six Bardos, a fundamental text of Tibetan Buddhism and a terma of the master Karma Lingpa. The six bardos describe all aspects of our human lives, including the process of death and dying. They provide us with an opportunity to discover how we can recognize all aspects of living and dying as an expression of our buddha nature, our limitless and true nature.
The Root Verses of the Six Bardos is published in the Collected Works of C.R. Lama in 2013 (Chapter 4), edited by James Low. The German edition was published in 2016 under the title „Gesammelte Schriften von Chimed Rigdzin Rinpoche”.
In the section “The six realms of Samsara”, James refers to a depiction of the Wheel of Existence that can be viewed here.