Having the mind fixed to a single object (cittekeggata, lit. ‘One-pointedness of mind’): this is concentration.
‘Right Concentration’ (samma-samadhi), in its widest sense, is the kind of mental concentration which is present in every wholesome state of consciousness (kusala-citta), and hence is accompanied by at least Right Thought (2nd factor), Right Effort (6th factor) and Right Mindfulness (7th factor).
‘Wrong Concentration’ is present in unwholesome states of consciousness, and hence is only possible in the sensuous, not in a higher sphere. Samadhi, used alone, always stands in the Sutta, for samma-samadhi, or Right Concentration.
The four ‘Foundations of Mindfulness’ (7th factor): these are the objects of concentration.
The four ‘Great Efforts’ (6th factor): these are the requisites for concentration.
The practising, developing and cultivating of these things: this is the development (bhavana) of concentration.
Right Concentration (samma-samadhi) has two degrees of development; 1. ‘Neighborhood Concentration’ (upacarasamadhi) which approaches the first absorption without, however, attaining it; 2. ‘Attainment Concentration’ (appanasamadhi), which is the concentration present in the four Absorptions (jhana). These Absorptions are mental states beyond the reach of the fivefold sense-activity, attainable only in solitude and by unremitting perseverance in the practice of concentration. In these states all activity of the five senses is suspended. No visual or audible impressions arise at such a time; no bodily feeling is felt. But, although all outer sense-impressions have ceased, yet the mind remains active, perfectly alert, fully awake.
The attainment of these Absorptions, however, is not a requisite for the realization of the four Supermundane Paths of Holiness; and neither Neighborhood-Concentration nor Attainment-Concentration, as such, possesses the power of conferring entry to the four Supermundane Paths: hence they really have no power to free one permanently from evil things.
The realization of the Four Supermundane Paths is possible only at the moment of deep ‘Insight’ (vipassana) into the Impermanency (aniccata), Miserable Nature (dukkhata) and Impersonality (anattata) of this whole phenomenal process of existence. This Insight, again, is attainable only during Neighborhood-Concentration, not during Attainment Concentration.
He who has realized one or other of the Four Supermundane Paths without ever having attained the Absorptions, is called Sukkha-vipassaka, or Suddhavipassana-yanika, i.e. ‘one who has taken merely Insight (vipassana) as his vehicle’. He, however, who, after cultivating the Absorptions, has reached one of the Supermundane Paths is called Saniathayanika, or ‘one who has taken Tranquillity (samatha) as his vehicle (yana)’. (Majjhima-Nikaya, 44)
The Four Absorptions (jhana)
Detached from sensual objects, detached from evil things, the disciple enters into the first Absorption, which is accompanied by Thought Conception and Discursive Thinking, is born of detachment, and filled with Rapture and Happiness.
This is the first of the Absorptions belonging to the Fine-Material Sphere (rupavacarajjhana). It is attained when, through the strength of concentration, the fivefold sense activity is temporarily suspended, and the five Hindrances are likewise eliminated. (Dîgha Nikaya, 22)
This first Absorption is free from five things, and five things are present. When the disciple enters the first Absorption, there have vanished (the five Hindrances): Lust, Ill-Will, Torpor and Sloth, Restlessness and Mental Worry, Doubts; and there are present: Thought Conception (vitakka), Discursive Thinking (vicara), Rapture (piti), Happiness (sukha), Concentration (citt’ekaggata = samadhi).
These five mental factors present in the first Absorption, are called Factors (or Constituents) of Absorption (jhananga). Vitakka (initial formation of an abstract thought) and vicara (discursive thinking, rumination) are called ‘verbal functions’ (vaci-sankhara) of the mind; hence they are something secondary compared with consciousness.
In Visuddhi-Magga, vitakka is compared with the taking hold of a pot, and vicara with the wiping of it. In the first Absorption both are present, but are exclusively focussed on the subject of meditation, vicara being here not discursive, but of an ‘exploring’ nature. Both are entirely absent in the following Absorptions.
And further: After the subsiding of Thought-Conception and Discursive Thinking, and by the gaining of inner tranquillity and oneness of mind, he enters into a state free from Thought-Conception and Discursive Thinking, the second Absorption, which is born of concentration (samadhi), and filled with Rapture (piti) and Happiness (sukha).
In the second Absorption, there are three Factors of Absorption: Rapture, Happiness, and Concentration.
And further: After the fading away of Rapture, he dwells in equanimity, mindful, with clear awareness: and he experiences in his own person that feeling of which the Noble Ones say: ‘Happy lives he who is equanimous and mindful’—thus he enters the third Absorption.
In the third Absorption there are two Factors of Absorption: equanimous Happiness (upekkha-sukha) and Concentration (citt’ekaggata).
And further: After the giving up of pleasure and pain, and through the disappearance of previous joy and grief, he enters into a state beyond pleasure and pain, into the fourth Absorption, which is purified by equanimity and mindfulness.
In the fourth Absorption there are two Factors of Absorption: Concentration and Equanimity (upekkha).
In Visuddhi-magga forty subjects of meditation (kammatthana) are enumerated and treated in detail. By their successful practice the following Absorptions may be attained:
All four Absorptions through Mindfulness of Breathing (see Vis. M. VIII. 3), the ten Kasina-exercises (Vis. M. IV, V.); the contemplation of Equanimity (upekkha), being the practice of the fourth Brahma-vihara (Vis. M. IX. 4).
The first three Absorptions: through the development of Loving-Kindness (metta), Compassion (karuna) and Sympathetic Joy (mudita), being the practice of the first three Brahma-viharas (Vis. M. IX. 1—3,).
The first Absorption: through the ten Contemplations of Impurity (asubha-bhavana; i.e. the Cemetery Contemplations, which are ten according to the enumeration in Vis. M. VI); the contemplation of the Body (i.e. the 32 parts of the body; Vis. M. VIII, 2); ‘Neighborhood-Concentration’ (upacara-samadhi): through the Recollections on Buddha, Dhamma and Sangha, on Morality, Liberality, Heavenly Beings, Peace (=Nibbana) and death (Vis. M. VI. VII); the Contemplation on the Loathsomeness of Food (Vis. M. XI. I); the Analysis of the Four Elements (Vis. M. IX. 2).
The four Immaterial Absorptions (arupa-jjhana or aruppa), which are based on the fourth Absorption, are produced by meditating on their respective objects from which they derive their names; Sphere of Unbounded Space, of Unbounded Consciousness, of Nothingness, and of Neither-Perception-Nor-Non-Perception.
The entire object of concentration and meditation is treated in Vis M. III-XIII (Majjhima-Nikaya, 43)
Develop your concentration: for he who has concentration, understands things according to their reality. And what are these things? The arising and passing away of corporeality, of feeling, perception, mental formations and consciousness. (Samyutta-Nikaya, XXII. 5)
Thus, these five Groups of Existence must be wisely penetrated; Ignorance and Craving must be wisely abandoned; Tranquillity (samatha) and Insight (vipassan ) must be wisely developed. (Majjhima-Nikaya, 149)
This is the Middle Path which the Perfect One has discovered, which makes one both to see and to know, and which leads to peace, to discernment, to enlightenment, to Nibbana. (Samyutta-Nikaya, LVI. II)
“And following upon this path, you will put an end to suffering.” (Dhammapada, 275)
Source: Nyanatiloka (compiler, translator). The Word of the Buddha: An Outline of the Teaching of the Buddha in the Words of the Pali Canon. 14th edition. Kandy, Ceylon: Buddhist Publication Society, 1967. (Pages 73-77) [This format has been produced by Alexander Peck.]