Concentration has three levels –
1. Kāmāvacara-khaṇika-samādhi: (momentary concentration in the sensory realm): The mind keeps thinking, coming to rest, and running along after skillful preoccupations – either internal or external – on the sensory level (kāmāvacara-kusala): sights, sounds, smells, flavors, tactile sensations, or ideas. An example of this is when the mind becomes quiet and rested for a moment as we sit chanting or listening to a sermon. In other words, the mind grows still for momentary periods in the same way that a person walks: One foot takes a step while the other foot rests on the ground, providing the energy needed to reach one’s goal. This is thus called momentary concentration, something possessed by people all over the world. Whether or not we practice concentration, the mind is always behaving this way by its very nature. This is called the bhavaṅga-citta or bhavaṅga-pāda: The mind stops for a moment and then moves on. In developing higher levels of concentration, we have to start out with this ordinary level as our basis. Otherwise, the higher levels probably wouldn’t be possible. Still, this level of concentration can’t be used as a basis for discernment, which is why we have to go further in our practice.
2. Rūpāvacara-upacāra-samādhi (threshold concentration in the realm of form): This refers to the first jhāna, in which the mind comes inward to rest on a single preoccupation within the body, fixing its attention, for example, on the in-and-out breath. When the mind stays with its one object, this is called ekaggatā. At the same time, there’s mindfulness keeping the breath in mind: This is called vitakka. The mind then adjusts and expands the various aspects of the breath throughout the entire body, evaluating them mindfully with complete circumspection: This is called alertness (sampajañña) or vicāra, which is the factor aware of causes and results. Mindfulness, the cause, is what does the work. Thus vitakka and vicāra cooperate in focusing on the same topic. We are then aware of the results as they arise – feelings of fullness, pleasure, and ease (pīti and sukha) for body and mind. At this point, the mind lets down its burdens to rest for a while, like a person walking along who meets with something pleasing and attractive, and so stops to look: Both feet are standing still, stepping neither forward nor back.
If we aren’t skilled enough to go on any further, we’ll then retreat. If we see results – such as signs and visions – arising in the mind, we may get excited and so cause our original preoccupation to waver or fade. Like a person sitting on a chair: If he sees something appealing in front of him, he may become so interested that he leans forward and reaches out his hand; he may even begin to budge a bit from his seat or stand up completely. In the same way, if we get engrossed in visions, thoughts, or views while we’re engaged in threshold concentration, we can become excited and pleased – we may even think that we’ve reached the transcendent – and this can cause our concentration to degenerate. If we try to do it again and can’t, we may then seize the opportunity to say that we’ve gone beyond the practice of concentration, so that we can now take the way of discernment – thinking, pondering, and letting go in line with nothing more than our own views and ideas. This, though, is not likely to succeed, because our knowledge has no firm basis or core, like a wheel with no axle or hub: How can it get anywhere? The power of threshold concentration, if we don’t watch after it well, is bound to deteriorate, and we’ll be left with nothing but old, left-over concepts.
3. Rūpāvacara-appanā-samādhi (fixed penetration in the realm of form): This refers to the practice of all four levels of rūpa jhāna. The first jhāna has five factors: directed thought, evaluation, fullness, pleasure, and singleness of preoccupation. The second jhāna has three: fullness, pleasure, and singleness of preoccupation. The third has two: pleasure and singleness of preoccupation; and the fourth has two: equanimity and singleness of preoccupation.
Fixed penetration in the realm of form means that the mind focuses on the internal sense of the body, remaining steadily with a single object – such as the in-and-out breath – until it reaches jhāna, beginning with the first level, which is composed of directed thought, evaluation, fullness, pleasure, and singleness of preoccupation.
When you see results arising, focus in on those results and they will then turn into the second jhāna, which has three factors: fullness, pleasure and singleness of preoccupation.
As your focus becomes stronger, it causes the sense of fullness to waver, so you can now let go of that sense of fullness, and your concentration turns into the third jhāna, in which only two factors are left: pleasure and singleness of preoccupation. The mind has few burdens; its focus is strong and the sense of inner light is radiant.
This causes the feeling of pleasure to waver, so that you can let go of that sense of pleasure, and the mind attains oneness in a very subtle preoccupation. The preoccupation doesn’t waver and neither does the mind. It stands firm in its freedom. This is called equanimity and singleness of preoccupation, which form the fourth jhāna. Mindfulness is powerful; alertness, complete. Both are centered on a single preoccupation without getting snagged on any other allusions or perceptions. This mental state is called the fourth jhāna, which has two factors: Equanimity is the external attitude of the mind; as for the real factors, they’re mindfulness and singleness, steady and firm.
The mind experiences a sense of brightness, the radiance that comes from its state of fixed penetration. Mindfulness and alertness are circumspect and all-round, and so give rise to skill and proficiency in practicing jhāna – in focusing, staying in place, stepping through the various levels, withdrawing, going back and forth. When the mind behaves as you want it to, no matter when you practice, only then does this truly qualify as fixed penetration, the basis for the arising of three qualities: intuitive knowledge (ñāṇa), discernment (paññā), and cognitive skill (vijjā).
Intuitive knowledge here refers to knowledge or sensitivity of an extraordinary sort. For example –
Pubbenivāsānussati-ñāṇa: the ability to remember previous lives.
Cutūpapāta-ñāṇa: the ability to focus on the death and rebirth of other living beings – sometimes in good destinations, sometimes in bad – together with the causes that lead them to be reborn in such ways. This gives rise to a sense of weariness and disenchantment with sensations and mental acts, body and mind.
Āsavakkhaya-ñāṇa: knowing how to put an end to the defilements of the heart in accordance with the knowledge – the clear vision of the four noble truths – that accompanies the particular transcendent path reached. And there are still other forms of extraordinary knowledge, such as iddhividhī, the ability to display supernormal powers, to make an image of oneself appear to other people; dibbasota, clairaudience; dibbacakkhu, clairvoyance – i.e., the ability to see objects at tremendous distances.
Discernment refers to discriminating knowledge, clear comprehension, knowledge in line with the truth. For example –
Attha-paṭisambhidā: acumen with regard to aims and results; thorough-going comprehension of cause and effect; knowing, for example, how stress is caused by ignorance and craving, and how the disbanding of stress is caused by the intuitive discernment that forms the Path; comprehending the meaning and aims of the Buddha’s various teachings and knowing how to explain them so that other people will understand – being able, for instance, to summarize a long passage without distorting its meaning.
Dhamma-paṭisambhidā: acumen with regard to mental qualities; knowing how to explain deep and subtle points so that other people will understand.
Nirutti-paṭisambhidā: acumen with regard to different languages. According to the texts, this includes knowing foreign languages and the languages of various other living beings by means of the eye of discernment (paññā cakkhu).
Paṭibhāṇa-paṭisambhidā: acumen with regard to expression; being fluent in making explanations and quick-witted in debate; knowing the most strategic way to express things.
All of these forms of discernment can arise from training the mind to attain fixed penetration. Vijjā – clear, open knowledge, free from any further concealments; and āloka – brilliance, radiance streaming out in all directions – enable us to see the true nature of sensations and mental acts, in accordance with our powers of intuitive discernment.
Cognitive skill refers to clear, uncanny knowledge that arises from the mind’s being firmly fixed in jhāna. There are eight sorts –
(1) Vipassanā-ñāṇa: clear comprehension of physical sensations and mental acts (rūpa, nāma).
(2) Manomayiddhi: psychic powers, influencing events through the power of thought.
(3) Iddhividhī: the ability to display powers, making one’s body appear in a variety of ways.
(4) Dibba-cakkhu: clairvoyance.
(5) Dibba-sota: clairaudience.
(6) Cetopariya-ñāṇa: the ability to know the mental states of other people.
(7) Pubbenivāsānussati-ñāṇa: the ability to remember previous lives.
(8) Āsavakkhaya-ñāṇa: the ability to put an end to the fermentations that defile the heart.
Thus, jhāna on the level of fixed penetration is extremely important. It can give us support on all sides – on the level of the world and of the Dhamma – and can bring success in our various activities, both in our worldly affairs and in our Dhamma duties, leading us on to the transcendent.
To summarize, there are two kinds of concentration:
1. That which gives rise to mundane knowledge: This is termed mundane concentration.
2. That which helps us to fulfill our duties on the level of the Dhamma, leading to vipassanā-ñāṇa or āsavakkhaya-ñāṇa, the knowledge that enables us – in accordance with the discernment and cognitive skills that arise – to abandon or cut off completely the mental currents tending in the direction of the fetters: This is termed transcendent concentration.