Samadhi is a term which is essentially a name for a state of consciousness beyond duality where subject and object of normal consciousness become annihilated. Samadhi is a term used both in Hinduism, mostly in the texts about Yoga, and Buddhism in different ways. Thelema's mystical philosophy relies largely on Samadhi, as well.

In Raja Yoga or Ashtanga (meaning eight-limbed), there are traditionally eight limbs (hence the name) of discipline. These are yama, niyama, asana, pranayama, pratyahara, dharana, dhyana, and samadhi. Samadhi can be seen as the final stage in the sequence called Samyama which is made up of dharana (concentration), dhyana (meditation), and samadhi, which literally means "establish, make firm" in Sanskrit.

"All the different steps in Yoga are intended to bring us scientifically to the superconscious state, or Samadhi. "
-Swami Vivekananda, Raja-Yoga

Vivekananda writes in his book Raja-Yoga, "The very fact that one man ever reached that state (Samadhi), proves that it is possible for every man to do so. Not only is it possible, but every man must, eventually, get to that state, and that is religion. Experience is the only teacher we have. We may talk and reason all our lives, but we shall not understand a word of truth, until we experience it ourselves."

Samadhi is the experience of the non-dualistic state of consciousness that one needs to directly experience.

In Buddhism, samadhi is 1 of 3 parts of Buddhist training. In this case, samadhi, or samatha, means "concentration." The other 2 parts of Buddhist training are sila (conduct/virtue) and panna (wisdom). Samadhi as 1 of 3 parts in Buddhist training contains Right effort, Right mindfulness, and Right concentration. Samadhi could also be specifically considered to be Right concentration. When one has achieved a strong and powerful concentration, one's mind is supposedly ready to penetrate and see into the ultimate nature of reality, which eventually leads to complete release from all suffering.

Essentially, both Hindu (Yogic) and Buddhist views of Samadhi view it as a pinnacle of concentration. In the Yoga traditions, this pinnacle of concentration allows one to enter into a state of non-dualistic consciousness. The Buddhist tradition seems to imply more that this concentration cuts through to the ultimate nature of reality - though this ultimate nature of reality could simply be coterminous with the Samadhic state of consciousness. The end-result of both is the dissolution of illusion and therefore sorrow.

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Liber AL , Chapter I:

I:13. I am above you and in you. My ecstasy is in yours. My joy is to see your joy.
I:14. Above, the gemmed azure is
The naked splendour of Nuit;
She bends in ecstasy to kiss
The secret ardours of Hadit.
The winged globe, the starry blue,
Are mine, O Ankh-af-na-khonsu!"

Commentary to AL I:14, "This Finite will evidently be an expression of the particular mood of its Father and Mother at the moment of its conception. Obviously, this "Child" cannot add to the Universe; it is therefore inevitably twin (Horus and Harpocrates, Osiris and Typhon, Jesus and Barabbas) in Nature, formed of equal and opposite elements. When the Operation is mystical in character, the "Child" does not appear at all in this manifested form as Two, but as Naught. In the consciousness of the Adept, this is called Samadhi. He has united himself with, and lost himself in, Nuit. When the "Child" appears as Two, it is Magick, as the other is Mysticism. This is the essential difference between these Arts."

I:22. Now, therefore, I am known to ye by my name Nuit, and to him by a secret name which I will give him when at last he knoweth me. Since I am Infinite Space, and the Infinite Stars thereof, do ye also thus. Bind nothing! Let there be no difference made among you between any one thing & any other thing; for thereby there cometh hurt.
I:23. But whoso availeth in this, let him be the chief of all!


Commentary to AL I:22, "This question of making "no difference" as ordained is to regard the whole of the non-Ego or universe apparently external to the Self as a single phenomenon; Samadhi on any one thing becomes therefore Samadhi on The Whole. The mystic who "availeth in this" can then perform his Great Work of "love under will" in a single operation instead of being obliged to unite himself with the non-Ego piecemeal."

I:26. "Then saith the prophet and slave of the beauteous one: Who am I, and what shall be the sign? So she answered him, bending down, a lambent flame of blue, all-touching, all penetrant, her lovely hands upon the black earth, & her lithe body arched for love, and her soft feet not hurting the little flowers: Thou knowest! And the sign shall be my ecstasy, the consciousness of the continuity of existence, the omnipresence of my body."

Commentary to AL I:26, "The prophet demanding a sign of his mission, it is promised; a Samadhi upon the Infinite."

I:27. Then the priest answered & said unto the Queen of Space, kissing her lovely brows, and the dew of her light bathing his whole body in a sweet-smelling perfume of sweat: O Nuit, continuous one of Heaven, let it be ever thus; that men speak not of Thee as One but as None; and let them speak not of thee at all, since thou art continuous!
I:28. None, breathed the light, faint & faery, of the stars, and two.
I:29. For I am divided for love's sake, for the chance of union.

Commentary to AL I:29, "It will be said that nobody can realize himself so long as the presentation is imperfect, that is, so long as he is incarnated. This is no doubt true in all rigour; but one can obtain an approximation to the intended self-knowledge by withdrawing for a time to the monistic form of self-consciousness, which does not distinguish between the Ego and the Non-Ego; in other words, by attaining Samadhi. But the first experience of Samadhi will then naturally be an ecstasy devoid of name or form, and containing no elements distinguishable as such; and we know this to be the case. One has simply deprived oneself of the means of expression, and all dual consciousness disappears, together with its forms, time and space. One concludes from this that the Universe is identical with the Ego, and all things dissolve into a formless essence characterized by knowledge and bliss. But this early stage of Samadhi is an illusion, a sort of drunken dizziness. (So in sexual love, the ecstasy abolishes the Ego, apparently; it forgets that duality was its cause, and must be equally real with itself, in one sense or another). But subsequent Samadhi teaches the adept that his universal instantaneous Unity exists as "None and Two"; and he learns that his Samadhi is peculiar to himself as well as common to all.

He becomes able to experience the truth of the statements in the Book of the Law, the nature of Nuith and Hadith, and of himself as a Star, unique, individual, and eternal, but yet a part of the Body of Nuith, and therefore identical with all other stars in that respect."

I:30. This is the creation of the world, that the pain of division is as nothing, and the joy of dissolution all.

Commentary to AL I:30, "As to "the joy of dissolution" the reference is to Samadhi, the trance in which Subject and Object become one. In this orgiastic ecstasy is experienced at first; later, the character of the consciousness changes to continuously calm delight, and later still, the delight deepens in a manner wholly indescribable. The technical terms used by Oriental Initiates to denote these conditions are untranslatable; in any case, they serve rather to darken counsel."

I:31. For these fools of men and their woes care not thou at all! They feel little; what is, is balanced by weak joys; but ye are my chosen ones.

I:44. For pure will, unassuaged of purpose, delivered from the lust of result, is every way perfect.
I:45. The Perfect and the Perfect are one Perfect and not two; nay, are none!
I:46. Nothing is a secret key of this law. Sixty-one the Jews call it; I call it eight, eighty, four hundred & eighteen.
I:47. But they have the half: unite by thine art so that all disappear.
I:48. My prophet is a fool with his one, one, one; are not they the Ox, and none by the Book?

Unite into the non-dualistic state of Samadhi. The "fool" is that state on undifferentiated consciousness and "one, one, one" or 111 is a number thereof and also of the destruction of the ego in Samadhi as explained in 777

I:52. If this be not aright; if ye confound the space-marks, saying: They are one; or saying, They are many; if the ritual be not ever unto me: then expect the direful judgments of Ra Hoor Khuit!

Commentary to I:58, "The certainty concerning death is conferred by the Magical Memory, and various Experiences without which Life is unintelligible. "Peace unutterable" is given by the Trance in which Matter is destroyed; "rest" by that which finally equilibrates Motion. "Ecstasy" refers to a Trance which combines these. "Nor do I demand aught in sacrifice" -- The ritual of worship is Samadhi."

Liber AL Chapter II:

II:9. Remember all ye that existence is pure joy; that all the sorrows are but as shadows; they pass & are done; but there is that which remains.

II:15. For I am perfect, being Not; and my number is nine by the fools; but with the just I am eight, and one in eight: Which is vital, for I am none indeed. The Empress and the King are not of me; for there is a further secret.

II:17. Hear me, ye people of sighing!
The sorrows of pain and regret
Are left to the dead and the dying,
The folk that not know me as yet.

II:23. I am alone: there is no God where I am.

Commentary to AL II:23, "The Atheism of God. "Allah's the Atheist! He owns no Allah." To admit God is to look up to God, and so not to be God. The cures of duality."

II:66. Write, & find ecstasy in writing! Work, & be our bed in working! Thrill with the joy of life & death! Ah! thy death shall be lovely: whososeeth it shall be glad. Thy death shall be the seal of the promise of our age long love. Come! lift up thine heart & rejoice! We are one; we are none.


Liber AL Chapter III:
AL III:17. Fear not at all; fear neither men nor Fates, nor gods, nor anything. Money fear not, nor laughter of the folk folly, nor any other power in heaven or upon the earth or under the earth. Nu is your refuge as Hadit your light; and I am the strength, force, vigour, of your arms.

Commentary to AL III:17, "The infinite unity is our refuge, since if our consciousness by in that unity, we shall care nothing for the friction of its component parts. And our light is the inmost point of illuminated consciousness... And the great Red Triangle is as a shield, and its rays are far-darting arrows!"

Aleister Crowley in Little Essays Toward Truth: Memory
"...no impression short of Sammasamadhi can ever pretend to confer any coherent idea of the Self."


Liber Aleph
"DE ECSTASIA SAMADHI, QUO ILLIS DIFFERIT."
Confuse thou not this beatific vision with the Trances called Samadhi; yet is Samadhi the Pylon of the Temple hereof. For Samadhi is the orgasm of the coition of the Unlike, and is commonly violent, even as the lightning cometh of the discharge between two vehicles of extreme difference of potentials. But as I shewed formerly concerning love, how each such discharge bringeth either component more nigh to equilibrium, so is it in this other matter, and by experience thou comest constantly to integration of love (or what not) within thyself, just as all effort becometh harmonious and easy by virtue of practice. Rememberest thou the first time thou was thrown into water, thy fear and thy struggles, and he vehemence of thy joy when first thou didst swim without support? Then, little by little all violence dieth away, because thou art adjusted to that condition. Therefore the fury of thine early victory in these arts magical and sciences is but the sign of thine own baseness and unworthiness, since the contrast or differential is so overwhelming to thee; but, becoming expert and adept, thou art balanced in the glory, and calm, even as the stars.


"DE ARTE AMORIS ET DELICIARUM MYSTICI."
The path therefore unto this beatific vision of beauty, o my Son, is that practice of Bhakti Yoga which is written in the book called Eight Score and Fifteen, or "Astarte", by this mine hand when I was in Gaul the beloved, at Montigny that is hard by the Forest of the Blue Fountain, with Agatha my concubine, the very soul of love and of musick, that had ventured herself from beneath the Cross Austral that she might seek me, to inspire and comfort me, and this was my reward from the masters, and consolation in the years of my sorrow. But the way that leadeth to the other form of this vision of beatitude, to with, science is Gnana Yoga or Raja Yoga, of which I have written only here and there, as one who should hrow great stones upon the earth in disorder, by default of building them nobly into a pyramid. And of this do I heartily repent me, and ask of the God Thoth that he may give me (albeit at the eleventh hour) virtue and with that I may compose a true book upon these ways of union. Thy first step, therefore, o my Son, is to attain unto Samadhi, and to urge thyself perpetually to repetition of thy successes therein, for it hath been said by philosophers of old that practice maketh perfect, and that manners, being the constant habit of life, maketh man.


"DE PRAEMIO SUMMO, VERA SAPIENTIA ET BEATITUDINE PERFECTA."
Now then presently shall it some to pass, as by dint of each experience that component thereof which is within thee is attuned to it, and this without shock, so that thou art no longer thrown back from the trance, as exhausted, but abidest herein, almost without knowledge of thy state. So then at last this Samadhi shall become normal to thy common consciousness, as it were a point of view. Thus all things shall appear to thee very continually as to one in his first love, by the vision of beauty, and by the vision of science thou shalt marvel constantly with joy unfathomable at the mystery of the laws whereby the Universe is upheld. This is that which is written: True wisdom and perfect happiness, o my son, it is in this contemplation that on hath the reward of he oath; it is by this that the tribulations are rolled away as a stone from thy tomb; it is with this that thou art wholly freed from the illusions of distinctions, being absorbed into he body of our Lady Nuith. May she grant thee this beatitude; yea, not to thee only, but to all that are.

Liber Astarte
40. Concerning the value of this particular form of Union or Samadhi. All Samadhi is defined as the ecstatic union of a subject and object in consciousness, with the result that a third thing arises which partakes in no way of the nature of the two.
It would seem at first sight that it is of no importance whatever to choose an object of meditation. For example, the Samadhi called Atmadarshana might arise from simple concentration of the thought on an imagined triangle, or on the heart.
But as the union of two bodies in chemistry may be endothermic or exothermic, the combination of Oxygen with Nitrogen is gentle, while that of Oxygen with Hydrogen is explosive; and as it is found that the most heat is disengaged as a rule by the union of bodies most opposite in character, and that the compound resulting from such is most stable, so it seems reasonable to suggest that the most important and enduring Samadhi results from the contemplation of the Object most opposite to the devotee. [On other planes, it has been suggested that the most opposed types make the best marriages and produce the healthiest children. The greatest pictures and operas are those in which violent extremes are blended, and so generally in every field of activity. Even in mathematics, the greatest parallelogram is formed if the lines composing it are set at right angles. ED.]
41. Conclusions from the foregoing. It may then be suggested to the Philosophus, that although his work will be harder his reward will be greater if he choose a Deity most remote from his own nature. This method is harder and higher than that of Liber E. For a simple object as there suggested is of the same nature as the commonest things of life, while even the meanest Deity is beyond uninitiated human understanding. On the same plane, too, Venus is nearer to man than Aphrodite, Aphrodite than Isis, Isis than Babalon, Babalon than Nuit.
Let him decide therefore according to his discretion on the one hand and his aspiration on the other; and let not one outrun his fellow.
42. Further concerning the value of this Method. Certain objections arise. Firstly, in the nature of all human love is illusion, and a certain blindness. Nor is there any true love below the Veil of the Abyss. For this reason we give this method to the Philosophus, as the reflection of the Exempt Adept, who reflects the Magister Templi and the Magus. Let then the Philosophus attain this Method as a foundation of the higher Methods to be given to him when he attains those higher grades.
Another objection lies in the partiality of this Method. This is equally a defect characteristic of the Grade.
43. Concerning a notable danger of Success. It may occur that owing to the tremendous power of the Samadhi, overcoming all other memories as it should and does do, that the mind of the devotee may be obsessed, so that he declare his particular Deity to be sole God and Lord. This error has been the foundation of all dogmatic religions, and so the cause of more misery than all other errors combined.
The Philosophus is peculiarly liable to this because from the nature of the Method he cannot remain sceptical; he must for the time believe in his particular Deity. But let him (1) consider that this belief is only a weapon in his hands, (2) affirm sufficiently that his Deity is but an emanation or reflection or eidolon of a Being beyond him, as was said in Paragraph 2. For if he fail herein, since man cannot remain permanently in Samadhi, the memorised Image in his mind will be degraded, and replaced by the corresponding Demon, to his utter ruin.
Therefore, after Success, let him not delight overmuch in his Deity, but rather busy himself with his other work, not permitting that which is but a step to become a goal. As it is written also, Liber CLXXXV.: "remembering that Philosophy is the Equilibrium of him that is in the House of Love."

Liber 333 - Book of Lies (falsely called)
"This is The Night wherein I am lost, the Love
through which I am no longer I."
-Chapter 15

"...the last paragraph [is] a reference to the nature of Samadhi.
As man loses his personality in physical love, so
does the magician annihilate his divine personality in
that which is beyond.
The formula of Samadhi is the same, from the
lowest to the highest. The Rosy-Cross is the Universal
Key. But, as one proceeds, the Cross becomes greater,
until it is the Ace, the Rose, until it is the Word."
-Commentary to Chapter 15

"THE STAG-BEETLE
Death implies change and individuality if thou be
THAT which hath no person, which is beyond the
changing, even beyond changelessness, what hast
thou to do with death?
The bird of individuality is ecstasy; so also is its death.
In love the individuality is slain; who loves not love?
Love death therefore, and long eagerly for it.
Die Daily."
-Chapter 16

"This seems a comment on the previous chapter; the
Stag-Beetle is a reference the Kheph-ra, the Egyptian
God of Midnight, who bears the Sun through the
Underworld; but it is called the Stag-Beetle to emphasise
his horns. Horns are the universal hieroglyph of energy,
particularly of Phallic energy.
The 16th key of the Tarot is "The Blasted Tower".
In this chapter death is regarded as a form of marriage.
Modern Greek peasants, in many cases, cling to Pagan
belief, and suppose that in death they are united to the
Deity which they have cultivated during life. This is "a
consummation devoutly to be wished" (Shakespeare).
In the last paragraph the Master urges his pupils to
practise Samadhi every day."
-Commentary to Chapter 16

"JOHN-A-DREAMS

Dreams are imperfections of sleep; even so is con-
sciousness the imperfection of waking.
Dreams are impurities in the circulation of the blood;
even so is consciousness a disorder of life.
Dreams are without proportion, without good
sense, without truth; so also is consciousness.
Awake from dream, the truth is known:(16) awake
from waking, the Truth is-The Unknown."
-Chapter 30

" This sum in proportion, dream: waking: : waking:
Samadhi is a favourite analogy with Frater P.,
who frequently employs it in his holy discourse.

NOTE: (16) I.e. the truth that he hath slept."
-Commentary to chapter 30

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"...When a man goes into Samadhi, if he goes into it a fool, he comes out a sage."
-Swami Vivekananda, Raja-Yoga

"This, in short, is the idea of Samadhi. What is its application? The application is here. The field of reason, or of the conscious workings of the mind, is narrow and limited. There is a little circle within which human reason must move. It cannot go beyond. Every attempt to go beyond is impossible, yet it is beyond this circle of reason that there lies all that humanity holds most dear. All these questions, whether there is an immortal soul, whether there is a God, whether there is any supreme intelligence guiding this universe or not, are beyond the field of reason. Reason can never answer these questions. What does reason say? It says, "I am agnostic; I do not know either yea or nay." Yet these questions are so important to us. Without a proper answer to them, human life will be purposeless."
-Swami Vivekananda, Raja-Yoga

"Samadhi is the property of every human being--nay, every animal. From the lowest animal to the highest angel, some time or other, each one will have to come to that state, and then, and then alone, will real religion begin for him. Until then we only struggle towards that stage. There is no difference now between us and those who have no religion, because we have no experience. What is concentration good for, save to bring us to this experience? Each one of the steps to attain Samadhi has been reasoned out, properly adjusted, scientifically organised, and, when faithfully practised, will surely lead us to the desired end. Then will all sorrows cease, all miseries vanish; the seeds for actions will be burnt, and the soul will be free for ever."
-Swami Vivekananda, Raja-Yoga

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Samadhi, by Paramhansa Yogananda (excerpts)
Vanished the veils of light and shade,
Lifted every vapor of sorrow,
Sailed away all dawns of fleeting joy,
Gone the dim sensory mirage...
As the sea exists without the waves,
But they breathe not without the sea.
Dreams, wakings, states of deep turia sleep,
Present, past, future, no more for me,
But ever-present, all-flowing I, I, everywhere.
Planets, stars, stardust, earth,
Volcanic bursts of doomsday cataclysms,
Creation’s molding furnace,
Glaciers of silent x-rays, burning electron floods,
Thoughts of all men, past, present, to come,
Every blade of grass, myself, mankind,
Each particle of universal dust,
Anger, greed, good, bad, salvation, lust,
I swallowed, transmuted all
Into a vast ocean of blood of my own one Being!
...Thou art I, I am Thou,
Knowing, Knower, Known, as One!
Tranquilled, unbroken thrill, eternally living, ever-new peace!
Enjoyable beyond imagination of expectancy, samadhi bliss!
Not an unconscious state
Or mental chloroform without wilful return,
Samadhi but extends my conscious realm
Beyond limits of the mortal frame
To farthest boundary of eternity
Where I, the Cosmic Sea,
Watch the little ego floating in Me...
From joy I came, for joy I live, in sacred joy I melt.
Ocean of mind, I drink all creation’s waves...
Myself, in everything, enters the Great Myself.
Gone forever, fitful, flickering shadows of mortal memory.
Spotless is my mental sky, below, ahead, and high above.
Eternity and I, one united ray.
A tiny bubble of laughter, I
Am become the Sea of Mirth Itself.