Prayer and Purity of Heart

The two conferences of Abba Isaac (Conferences 9 and 10) are the spiritual summit of Cassian’s Conferences: a sustained teaching on prayer that moves from its kinds and degrees to the demand of unceasing prayer, and culminates in a single monologistic formula — the verse “O God, come to my assistance; O Lord, make haste to help me” — given for ceaseless repetition. Underlying all of it is the governing idea of the whole work, purity of heart (puritas cordis), the proximate goal of the ascetic life named in Conference 1. This file expounds Isaac’s teaching and weighs, carefully, the much-discussed claim that it forms a Western bridge toward later hesychasm and the Jesus Prayer.

Tradition: Pan-Orthodox (pre-Schism; transmitter of Egyptian monasticism to the West)

Purity of Heart as the Proximate Goal

Cassian’s theology of prayer cannot be read apart from the program he lays down in the very first conference. There Abba Moses distinguishes the scopos of the monastic life — its immediate, proximate goal — from its telos, its ultimate end. The telos is the Kingdom of God and eternal life; but no one reaches the end except by way of the proximate goal, and that goal is purity of heart (puritas cordis) (Conferences 1.4–5; trans. Ramsey, ACW 57). Every ascetic labor — fasting, vigil, poverty, the recitation of the psalms, the reading of Scripture — is an instrument, valuable only insofar as it conduces to purity of heart; pursued for its own sake it becomes an idol (Conferences 1.7; Ramsey 1997). Moses grounds the principle in the Lord’s word to Martha, that Mary has chosen the “good part” — the contemplative attention to God — which will not be taken from her (Conferences 1.8, citing Luke 10:42; Ramsey 1997).

The phrase puritas cordis is Cassian’s Latin rendering of the Evagrian apatheia — the state of a heart no longer ruled by the disordered passions, and therefore free to attend to God (Stewart 1998; Chadwick 1968). Cassian deliberately avoids the Greek term, whose connotation of “impassibility” was suspect to Latin ears, and substitutes a biblical phrase rooted in the Beatitude: “Blessed are the pure in heart, for they shall see God” (Matthew 5:8). Purity of heart is thus both the precondition of true prayer and the very thing prayer expresses and deepens; the doctrine of prayer in Conferences 9–10 is the unfolding of the doctrine of purity of heart in Conference 1.

Abba Isaac’s First Conference: The Kinds of Prayer (Conf. 9)

The ninth conference opens by tying prayer to the goal already established: the whole purpose of the monk, Isaac says, is the perpetual and uninterrupted perseverance in prayer, and toward this immovable tranquility of mind all his labors tend (Conferences 9.2; Ramsey 1997). The end of every monk and the perfection of his heart is a continual and unbroken constancy in prayer — which is, in other words, purity of heart in act (Conferences 9.2; Stewart 1998).

Isaac then orders prayer according to the fourfold scheme drawn from the Apostle, who in 1 Timothy 2:1 names “supplications, prayers, intercessions, and thanksgivings” (Conferences 9.9–15; Ramsey 1997, citing 1 Timothy 2:1). Cassian’s Isaac correlates these four with stages of the spiritual life — supplications arising from compunction over sin, prayers from the offering of vows, intercessions from charity for others, and thanksgivings from the contemplation of God’s benefits — and teaches that the maturing soul passes through and ultimately gathers them up (Conferences 9.9–17; Stewart 1998).

Above and through all four stands the prayer the Lord Himself gave, the Our Father, which Isaac expounds as the model and pattern of all Christian prayer (Conferences 9.18–24; Ramsey 1997, on Matthew 6:9–13). And beyond even the words of the Lord’s Prayer Isaac points to a still higher state: a prayer that transcends speech and concept altogether, the “fiery prayer” (oratio ignita) — a prayer “which is known and experienced by very few,” in which the mind, enkindled and lifted beyond the senses and beyond all words, pours itself out to God in an ineffable ardor (Conferences 9.25–26; Ramsey 1997; Stewart 1998). This wordless, fiery prayer is the goal toward which the disciplined forms ascend; it cannot be manufactured, only received.

Abba Isaac’s Second Conference: Unceasing Prayer (Conf. 10)

The first conference of Isaac leaves Cassian and Germanus with a difficulty, and the tenth conference is the answer to it. How, the two visitors ask on returning, can the mind possibly hold to God without ceasing, when it is so easily scattered by a multitude of thoughts and wanders even in the moment of prayer (Conferences 10.8; Ramsey 1997)? The scriptural mandate is plain — the Apostle commands, “Pray without ceasing” (1 Thessalonians 5:17) — but its practice seems impossible for a mind that cannot stay still. Isaac’s reply is the most influential passage Cassian ever wrote.

The Monologistic Formula

Isaac gives the monks a single short verse to carry constantly, a “formula for contemplation” by which the mind may be recalled to God in every circumstance and held to a single thought. The verse is from the Psalms:

Deus in adiutorium meum intende; Domine ad adiuvandum me festina.
“O God, come to my assistance; O Lord, make haste to help me.”

This is Psalm 69:2 in the Greek Septuagint and the Latin Psalter that follows it — Psalm 70:1 in the Hebrew and most English numbering (Conferences 10.10; Ramsey 1997). Isaac commends this verse above all others as the one to be repeated ceaselessly: it is to be said in adversity, that one may be delivered, and in prosperity, that one may be preserved from pride; in temptation, in fear, in dryness, in the very heat of carnal assault, in sorrow and in joy alike — there is no condition of the spiritual life, Isaac teaches, to which this single cry is not perfectly fitted (Conferences 10.10; Ramsey 1997). The monk is to turn it over unceasingly in his heart, “going to sleep” upon it and “waking” upon it, until it becomes the constant occupation of the mind, displacing the crowd of wandering thoughts by its own continual repetition (Conferences 10.10; Stewart 1998).

This is monologistic prayer in the strict sense: a single brief formula (monologistos, “of one word” or one phrase), repeated without ceasing until it sinks below deliberate effort and becomes the abiding disposition of the heart. Isaac explains the spiritual mechanism: by confining the mind to “the poverty of this little verse,” one starves the multitude of distracting thoughts and attains, through that very poverty, the gospel beatitude of the poor in spirit (Conferences 10.11; Ramsey 1997). The reduction of prayer to one short, constantly repeated phrase is precisely what makes ceaseless prayer possible for a mind otherwise unable to remain fixed.

From Formula to Fire

The monologistic verse is not, for Isaac, the summit but the disciplined road to it. Held faithfully, the little verse purifies and concentrates the mind until, enriched by it, the soul rises to that wordless, “fiery” prayer described at the close of the ninth conference — the prayer beyond words and images in which the heart is wholly absorbed in God (Conferences 10.11; 9.25; Stewart 1998). The continual repetition is the means; the unceasing remembrance of God and, beyond it, the fiery and imageless prayer are the fruit. Cassian’s teaching thus joins a concrete, repeatable practice to a high apophatic goal: the monk does something definite with his mind at every moment, and that doing opens onto a receiving he cannot command.

The Later Western Office

The very verse Isaac commends had, by Cassian’s own report, a place in the desert’s psalmody, and it would acquire a permanent one in the West. St. Benedict, drawing on Cassian, prescribes “O God, come to my assistance; O Lord, make haste to help me” as the opening versicle of nearly every Hour of the Divine Office, so that the Western Church to this day begins its canonical prayer with the formula Abba Isaac gave for ceaseless repetition (Rule of St. Benedict 18; Chadwick 1968; see Influence on Benedict). What Cassian transmitted as a private monologistic practice the Latin Office absorbed into its corporate prayer.

The Bridge Toward Hesychasm and the Jesus Prayer

Because Cassian teaches a short formula, repeated without ceasing, in order to still the wandering mind and attain unbroken remembrance of God and a wordless prayer of the heart, his teaching has long been compared with the hesychast tradition of the Christian East and, specifically, with the Jesus Prayer — “Lord Jesus Christ, Son of God, have mercy on me, a sinner” — repeated continually in the same monologistic manner toward the same goal of unceasing prayer and purity of heart (see The Jesus Prayer; Purity of Heart and Hesychasm).

The structural parallels are real and striking: a single brief formula; ceaseless repetition; the deliberate “poverty” of confining the mind to one phrase to starve distraction; the goal of continual remembrance of God; and the opening onto a wordless, “fiery” prayer of the heart that cannot be self-generated. Cassian and the hesychast masters draw, moreover, on a common patrimony — the prayer-theology of Evagrius and the Egyptian desert — so the kinship is genealogical and not merely coincidental.

Yet the claim must be stated with care, for two distinct things can be meant by it. [Disputed: the strength of the genealogical claim is contested. The careful position — represented by Columba Stewart (*Cassian the Monk*, 1998) and by Metropolitan Kallistos Ware in his writings on the Jesus Prayer and the *Philokalia* — is that Cassian's monologistic formula is best read as a Western *parallel* or *precursor* drawn from the same Evagrian-desert root, not as the direct ancestor of the Jesus Prayer; the two practices differ decisively in content (a Psalm verse, *Deus in adiutorium*, versus the invocation of the Name of Jesus), and no continuous line of transmission runs from Cassian's verse to the Byzantine Jesus Prayer. A stronger claim — that Cassian directly anticipates or stands in the line of descent of hesychast prayer — overstates the evidence by sliding from genuine structural and ancestral kinship to direct dependence.] The sober conclusion is that Cassian and the hesychasts are cousins in a shared desert inheritance: his teaching shows that the monologistic recall of the mind to God and the goal of unceasing prayer were not Byzantine inventions but the common possession of fourth- and fifth-century monasticism, East and West — which is itself a significant point for an Orthodox reading of this Latin-writing, Greek-thinking father.

References

Cassian, John. The Conferences. Translated and annotated by Boniface Ramsey. Ancient Christian Writers 57. New York: Paulist Press, 1997. (Abba Moses on scopos/telos and purity of heart at 1.4–8; Isaac’s first conference on the kinds of prayer at 9.2, the four types from 1 Timothy 2:1 at 9.9–17, the Lord’s Prayer at 9.18–24, and the oratio ignita at 9.25–26; Isaac’s second conference on unceasing prayer at 10.8, the formula Deus in adiutorium meum intende [Ps 69:2 LXX / 70:1] at 10.10, and the “poverty of the little verse” at 10.11.)
Cassian, John. The Conferences (Conlationes). Translated by Edgar C. S. Gibson. Nicene and Post-Nicene Fathers, Series II, Vol. 11. New York: Christian Literature Company, 1894. (Public-domain translation of Conferences 9–10 with the same internal divisions.)
Stewart, Columba. Cassian the Monk. Oxford Studies in Historical Theology. New York: Oxford University Press, 1998. (Purity of heart as Cassian’s rendering of apatheia; the analysis of Conferences 9–10; the monologistic formula and the question of its relation to later hesychast prayer.)
Chadwick, Owen. John Cassian. 2nd ed. Cambridge: Cambridge University Press, 1968. (The theology of prayer; Deus in adiutorium and its passage into the Benedictine Office.)
Ware, Kallistos. The Power of the Name: The Jesus Prayer in Orthodox Spirituality. Oxford: SLG Press, 1974; and the introduction to The Philokalia, Vol. 1, trans. G. E. H. Palmer, Philip Sherrard, and Kallistos Ware (London: Faber and Faber, 1979). (The Jesus Prayer and the wider tradition of monologistic prayer within which Cassian’s formula is read as a Western parallel.)
The Rule of St. Benedict. Chapter 18. (Prescribes Ps 69:2 LXX / 70:1, “O God, come to my assistance,” as the opening versicle of the canonical Hours, drawing on Cassian.)