Mystical Union

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In the closing pages of the treatise that Porphyry placed last in the sixth and final group of his teacher’s writings, Plotinus reaches for an image and then abandons it. The soul that has climbed past every form, he says, no longer sees, no longer holds two things apart, but has become one with what it sought — and the chapter ends on a phrase that became, almost alone among his many thousands of lines, the one sentence people remembered: the flight of the alone to the Alone. Porphyry adds a biographical note that the philosophy itself never claims. In the years he studied with him, he writes, Plotinus reached that union four times.

That terminus — the soul arriving at the divine and, in arriving, ceasing in some manner to be merely itself — recurs across traditions that share no scripture and, for long stretches, no contact. Each names it differently. Each guards it differently. And the most disputed question about it is whether the differences go all the way down.

A Roman sarcophagus, third century, whose seated reader has been identified with Plotinus surrounded by his circle. — via Wikimedia Commons (public domain)

The forms of the one terminus

The Greek word is henosis, “becoming one,” and in the Platonism that runs from Plotinus through Proclus it is the goal toward which the whole discipline of Neoplatonism bends. The soul ascends by stripping: away from sensation, away from discursive reason, finally away even from the nous, the intellect that contemplates the eternal Forms. Above the intellect stands the One, the source that is beyond being and beyond knowledge because knowledge requires a knower set over against a known, and the One admits no such division. Union with it cannot therefore be a seeing. In Ennead VI.9, translated for English readers by Stephen MacKenna, Plotinus describes a state in which the soul “neither sees, nor distinguishes by seeing, nor imagines that there are two,” but has become one with the One as concentric circles collapse into a single center. This is the structural template the West would inherit: ascent by negation, a summit beyond concept, a union that is not the grasp of an object but the loss of the gap.

Christianity received that template and crossed it with a different text. The unio mystica of the Latin and Greek churches has two great vocabularies, and they pull in opposite directions. One is erotic. Reading the Song of Songs as an allegory of the soul and God, Bernard of Clairvaux preached eighty-six sermons on the book and never finished it, halting near the start of the third chapter; in them the soul is the bride and Christ the bridegroom, and union is the osculum, the kiss of the mouth, the consummation of a mutual desire in which, by grace, God comes to want the soul as the soul wants God. This bridal mysticism, taken up by the Cistercians and later by the Beguines and the women contemplatives of the thirteenth century, kept the union personal: two who become one in love remain, in love, two.

The other vocabulary is more vertiginous. The Rhineland Dominican Meister Eckhart preached not a marriage but a birth — the Geburt, the eternal generation of the Word, occurring not only in the Trinity but in the soul itself, in a point he called by many names: the Fünklein or little spark, the scintilla animae, the citadel, and above all the grunt, the ground. In that ground, Eckhart taught, the soul and God share a single floor; the spark is “uncreated and uncreatable,” never wholly severed from the Godhead. The union here is not affection across a distance but recognition of an identity that distance had concealed — and the claim that something in the creature is uncreated was among the propositions condemned in the bull In agro dominico of 1329, the year after Eckhart’s death.

Gian Lorenzo Bernini’s Ecstasy of Saint Teresa, completed 1652, Santa Maria della Vittoria, Rome — the angel and the transverberated heart of the saint who mapped the soul’s interior as seven rooms. — via Wikimedia Commons (CC BY-SA)

A different cartography came from sixteenth-century Spain. Teresa of Ávila figured the soul as a crystalline castle of seven concentric dwellings, the moradas of her Interior Castle, with God enthroned in the innermost. The sixth dwelling is the spiritual betrothal, all longing and ecstatic disturbance; the seventh is the spiritual marriage, where the disturbance ends. There, she wrote, the union is permanent and the soul is given an image: rain that has fallen into a river can no longer be drawn back out and divided from it, or light entering a room through two windows that arrives as one light. Her companion in the Carmelite reform, John of the Cross, supplied the dark side of the same ascent. His Noche oscura and the Ascent of Mount Carmel chart the soul’s passage to union not as a climb into light but as a stripping in darkness — the active and then the passive night of sense and of spirit — governed by his repeated nada, nothing, nothing, nothing, the via negativa of apophatic theology bent into a discipline of the heart. Both Carmelites drank from the same well as Eckhart: the Mystical Theology of Pseudo-Dionysius, whose “brilliant darkness” had defined Christian unknowing since around the year 500.

Islamic Sufism names the terminus with a paired movement. Fanāʾ is the passing-away of the servant’s egoic attributes; baqāʾ is the abiding, the subsistence-after-passing in which the servant returns clothed in the attributes of God. The Quranic anchor is the verse that all upon the earth passes away while the Face of the Lord remains, and the early systematizer was Abū Saʿīd al-Kharrāz at the end of the ninth century. The crucial refinement belongs to Junayd of Baghdad: a “second sobriety,” a return from the drunkenness of union to lucid function, vision intact, able to teach. Junayd’s reading also defused the tradition’s most litigated utterance — al-Ḥallāj’s anā al-ḥaqq, “I am the Real,” for which he was executed in Baghdad in 922. Such ecstatic cries, the shaṭḥiyyāt, were not, on this account, propositions of identity but speech wrung from a servant whose attributes had been replaced by God’s, on the logic of the divine saying that God becomes the hearing and the sight of the one He loves. To read them as flat identity would be to fall into ḥulūl, incarnationism, or ittiḥād, fusion — both heresies. The Andalusian Ibn ʿArabī seems to push hardest toward identity in the doctrine his later commentators would call waḥdat al-wujūd, the oneness of being; yet as William Chittick has patiently shown from the Futūḥāt al-Makkiyya, even there the gnostic must hold incomparability and similarity in a single two-eyed gaze, never collapsing into one pole. The same terminus animates the Persian poetic tradition, where the moth in the flame became its standing emblem.

Jewish mysticism is the tradition that most insists the gap remain. Its word is devekut, “cleaving,” and its root sits in Deuteronomy’s repeated command to cleave to the Lord. In the Kabbalah and then, democratized, in Hasidism — where the early masters held that any Jew might attain it through prayer turned wholly toward God — devekut means constant adhesion, the mind kept always on the divine, sometimes rising to ecstasy. But Gershom Scholem, the historian who recovered the field for the modern academy, stressed that devekut is precisely not the Hebrew equivalent of the Christian unio mystica. The creature cleaves; it does not merge. Adhesion is intimacy held just short of fusion, and the reticence is doctrinal, not a failure of nerve — the same instinct that runs through Jewish negative theology, guarding the incommensurability of the infinite. The Vedantic traditions, for their part, raise the stakes furthest in one school and lower them sharpest in another: Śaṅkara’s Advaita reads the great Upaniṣadic sayings — tat tvam asi, “that thou art” — as disclosing an identity of self and Brahman that was always the case and needed only to be recognized, while the qualified non-dualism of Rāmānuja and the dualism of Madhva insist the liberated soul keeps its distinctness even at the summit. “Vedānta” is not one position on union but three incompatible ones, a fact the modern presentations of Neo-Vedānta tend to soften.

Absorption, love, and the discipline of distinction

Set the forms beside one another and a fault line appears that does not respect the borders between religions. It runs between two answers to a single question: in union, does the soul become the divine, or is it joined to the divine while remaining itself?

On one side stands union as absorption — the drop in the ocean, the circle’s center merged, Eckhart’s grunt where God and soul share one floor, Śaṅkara’s recognition that the apparent two were never two. On the other stands union as the consummation of love or the alignment of wills — the bride and bridegroom of Bernard, the devekut that cleaves without dissolving, the baqāʾ in which the servant subsists with God’s attributes yet remains the servant, Rāmānuja’s soul that shares Brahman’s bliss without losing its face. The medieval scholastics had a name for the milder claim, unio mystica as the conforming of the creature’s will to God’s; Bernard McGinn distinguishes that from Eckhart’s stronger unitas indistinctionis, a union of indistinction in the ground.

What looks at first like the same experience differently labeled turns out, on inspection, to be defended by load-bearing distinctions that each tradition refuses to surrender. Eastern Christian hesychasm and the doctrine of deification it defends rest on Gregory Palamas’s distinction between God’s imparticipable essence and His uncreated energies: the saint is genuinely deified, made god by grace and not by nature, sharing the energies while the essence stays forever beyond reach. Take that distinction away and deification collapses into pantheism, which the tradition treats as the loss of the doctrine rather than its purification. Sunni Sufism guards the asymmetry of Lord and servant against ḥulūl and ittiḥād with the same vigilance. Advaita alone seems to let the gap go entirely — and even there the modern Advaitin Anantanand Rambachan argues that scripture, not private experience, is the means of knowing Brahman, which quietly relocates the union away from a reportable mystical event. The closer one reads, the more the traditions look less like dialects of one tongue and more like distinct languages that happen to have a word in roughly the same place.

This is the apophatic discovery turned outward. Just as each tradition empties its concepts to approach a summit beyond concept, so the comparison of the summits empties the easy assumption that they are one. The dark night, the neti neti of “not this, not this,” the Dionysian unknowing, the fanāʾ of the attributes — these are recognizably cousins. But the soul that emerges from the night into Teresa’s spiritual marriage is still a creature loved by a personal God; the self that recognizes Brahman in Advaita was never a separate creature at all. The grammar of the ascent rhymes. The grammar of the arrival does not.

Raphael’s School of Athens, 1509–1511, Vatican: Plato at the center gestures upward, toward the One that Plotinus made the goal of the soul’s flight. — via Wikimedia Commons (public domain)

The modern study and the long argument

For most of its history the doctrine of union was an internal affair, taught from master to disciple inside a single frame. The modern study of mysticism began when scholars stepped outside every frame at once and asked what, if anything, the reports had in common. The founding gesture was psychological. In The Varieties of Religious Experience, his Gifford Lectures of 1901–02, William James proposed four marks of the mystical state — ineffability, a noetic quality, transiency, passivity — and treated it as a deliverance of private experience, a Protestant individualism that nearly every successor has had to correct. Friedrich von Hügel answered almost at once that mysticism untethered from institution and intellect becomes “dangerous error.” The Anglican Evelyn Underhill, in her 1911 Mysticism, mapped a fivefold mystic way — awakening, purgation, illumination, the dark night, the unitive life — that still organizes spiritual-direction literature even where her implicit perennialism is now read as a period mark.

Out of this grew the central twentieth-century quarrel, and it is the quarrel the doctrine of union now lives inside. On one side, the perennialist or common-core reading. In Mysticism and Philosophy (1960), W. T. Stace argued that beneath the local vocabularies lies a universal phenomenology — at its deepest an introvertive “unitary consciousness,” contentless yet awake — onto which each tradition lays its own concepts after the fact. Aldous Huxley had popularized a kindred thesis: one experience, many names; the traditions are dialects of a single perennial philosophy. On the other side, the constructivist reading. In a 1978 essay that reset the field, “Language, Epistemology, and Mysticism,” Steven T. Katz denied that there are any unmediated experiences at all. The mystic’s prior scheme — doctrine, scripture, training, expectation — shapes the experience itself, so that the Buddhist’s emptiness and the Jewish devequt are not two versions of one state but two different states. There is no neutral place to stand from which the experience could be checked against the interpretation, because the interpretation reaches all the way in.

The argument has not been settled, and a responsible account presents it without choosing. Between the poles sit the qualifications. Robert Forman and his collaborators replied to Katz with the “pure consciousness event” — a state so empty of content that prior concepts have nothing to build, drawing evidence from Eckhart’s vergezzen, his forgetting, and from the deepest samādhi of Patañjali; the field has come to accept the soft version (such states occur) more readily than the hard one (they are foundational and everywhere the same). John Hick built a Kantian pluralism in which a single transcendent Real is filtered through culturally shaped categories into the many personal and impersonal absolutes. And the most exacting comparativists — McGinn on the Christians, Chittick on Ibn ʿArabī, Scholem on the Kabbalah, Rambachan on Advaita — have tended to work by a method that cuts against the perennialist grain: first establish what each tradition will not let go of, and only then ask what structure survives the comparison.

What survives, on that method, is neither a single shared experience nor a heap of unrelated ones. It is a precise map of where the rhymes are real — the apophatic registers, the languages of participation, the asymmetry between the finite and the infinite that almost every tradition stations a guard to protect — and where the load-bearing distinctions diverge too far to be assimilated. Theosis keeps the energies and surrenders the essence; fanāʾ and baqāʾ keep the servant inside the union; devekut cleaves and will not merge; Vedānta fractures into three metaphysics that genuinely disagree. To honor those refusals is to learn something the flattened version cannot teach: that a tradition’s insistence on what it will not give up is itself a report about the terminus, and that the most cross-cultural thing in the whole comparison may be the resolve, in each tradition, not to be confused with any other.

→ In the library: Plotinus, Enneads (MacKenna translation) · Enneads VI.9 — On the Good, or the One (MacKenna)

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