The Four Jhanas and the Formless Realms:
- Delightful Sensations
- Utter peacefulness
- Infinity of space
- Infinity of consciousness
- Neither perception nor non-perception
(from Anguttara Nikaya 9.36)
The jhanas are the main part of Right Concentration in The Noble Eightfold Middle Path. The insight of vipassana meditation can be found in Right Concentration as well, but is primarily part of Right Effort and Right Mindfulness of the Eightfold Middle Path. The jhanas were well known during the time of the Buddha and before. The teachers the Buddha studied under before his enlightenment were all familiar with the jhanas and taught him how to get to the first seven and then eighth jhana. But, the Buddha discovered that there was more to be known. He knew that the jhanas were not all that there is.
The five hindrances to meditation which prevent access to entering the jhanas can be eliminated by the five factors of the first jhana. The first factor is one-pointedness concentration. By maintaining one-pointedness concentration, you will not get distracted by sense pleasures or desires. Focus on your meditation subject, which is usually the breath. There are 40 meditation subjects for Right Concentration and any of them can allow access to the jhanas, but the common subject for most meditators is the breath. When rapture and joy become noticeable, this eradicates the hindrance of aversion. The happiness and comfort that follows eradicates restlessness and worry. As the concentration gets stronger you aim very well at your subject and this eliminates sloth and torpor. Since skeptical doubt includes indecision, as you start to have sustained attention, the doubt about the practice fades.
Some teachers only place the first four jhanas under the heading of 'Jhana' and the remaining four to five as the "formless absorptions" or as the "formless realms." For ease in seeing the transition from one jhana to the next, all nine are labeled as 'jhanas' since they are all inter-connected and are all mental, meditative absorptions. In the Suttas of the Tipitaka the first four are labeled as 'jhanas' but are always followed by the remaining formless realms.