Navel fire warm happy self-burning(2)
With regard to “mystic heat”, the following explanations are most common: “the most superior method that uses strong fire to burn off all unclean content, kingdom, and place, ultimately extinguishing all frustrations and wrong-thinking, from which the empty happy dual-practice wisdom then swiftly arises. Vajra Heart Essence Explanation states “can burn, therefore it is called strong fire”. Ocean-arise Hevajra Explaining Difficulties mentions “only strong fire can extinguish all frustration”. Naropa Explaining Difficulties mentions “it can make powerful career, therefore it is explained as strong”. Nonscaring Argument Explanation mentions “because it has been said that it is certain that strong fire is the self nature with the perfection of superior wisdom and the Ah character is great mercy, these two things can lead to the ultimate no-discarding status, therefore it is strong fire”. In Equal to Emptiness Tantra, it is divided into three types. One: external strong fire, which is also called the self-nature strong fire or superior meaning strong fire, i.e. the empty self nature of all dharma announce the superior wisdom empty nature, causing the heart of 80 self natures to dissolve into all emptiness. As Master Gampopa said “the great seal is the strong fire”. Two: internal strong fire, referring to the mystic heat induced by the short Ah in the navel. This is the practical meditation method as mentioned later in this text. Three: secret strong fire, also called the combining strong fire, i.e. it arises from the dual practice and combination of all deep superior empty nature with unchanging great joy. It can combine into the ultimate unchanging status of great joy. In addition, there are many sorting methods, as in Teaching Spike, it is divided into karma, yoga, and co-living strong fire; in Equal to Emptiness Tantra it is divided into 12 kinds. Besides these, there are many other methods of classification, here we will not talk redundantly.
Meditators mainly focus on internal strong fire (i.e. mystic heat), and some meditate external strong fire and secret strong fire after completing meditation on internal strong fire. Cuoru Cilang states in A Brief History of the Kagyu Lineage of Tibetan Buddhism “Meditating the first, because it can reach the point after combining with the most superior strong fire, can induce the experience of the latter two. Therefore, not shaking in the belief of meditating and studying secret strong fire, turning internal and external strong fire into branches of Tao can become superior meditation, therefore, the direction is according to the root step.”