There is one thing that I usually do not do and that is recommend any book on Prayer of the Heart. This is not really a “book topic,” though there are some very beautiful texts in the Eastern Orthodox tradition that approach this topic through a consideration of the mantric Jesus Prayer. Nothing wrong with drinking deeply from such sources, but what I would advise and warn against is taking a “methodical” approach to the Prayer of the Heart and ignoring the deeply personal nature and manifestation of it in different people’s lives in very unique circumstances. There is no method, no way, no formula, no path that “leads” to the Prayer of the Heart. Classic Christian sources and even Sufi sources (which also present the Prayer of the Heart) can be misleading because they couch their language precisely in terms of “steps,” “methods,” “stages,” etc. There is a reason for such language but we won’t get into that here. Those who have been exposed to the great Asian traditions also can become enamored with a kind of technical approach to the spiritual life–understandable in certain contexts but could be very misleading in regard to the Prayer of the Heart. In its utter essence the Prayer of the Heart has to do with the unfolding of one’s deepest identity in God and that will always be beyond any formulation or any program, even of a spiritual master or saint. You are you, and there is absolutely no one like you, and finding God in that “youness”(or I should more accurately say “I-ness”) is the essence of Prayer of the Heart.
Having said all this I now want to recommend a little book: Prayer of the Heart in Christian & Sufi Mysticism by Llewellyn Vaughan-Lee. It is not a great book; certainly not the “last word” on this topic; but it is a beautiful and charming little book filled with many great insights and introducing one to this great topic from several different directions. I would not agree with everything in this book, but it seems to fill a real need in bringing the notion of Prayer of the Heart to a contemporary audience. The really special quality of this little book is that it discusses Prayer of the Heart from both the Christian perspective and the Sufi perspective. Just my opinion, but I think that the Sufis go deeper into this than we do, and I have learned much from what little I have been exposed to. But just as with us there is this tendency to articulate the “journey” into a kind of methodical “cookbook” approach. This is not the essence of what they teach but it is important for the Sufi follower and we need to respect their language. In this little book the author, Vaughan-Lee, a Sufi member but also knowledgeable in Christian mysticism, spends a considerable time using Teresa of Avila as a source for his presentation. Teresa is not one of my favorites, but she is truly a master of Christian mysticism. I never could quite connect with her language about “mansions” and “stages of prayer” and all that kind of stuff, but it turns out that Sufis are quite at home there! So be it.
The book begins with a marvelous Sufi word:
“God Most High hath brought forth creation and said,
​‘Entrust Me with your secrets.
If you do not do this, then look toward Me.
If you do not do this, then listen to Me.
If you do not do this, then wait at My door.
​If you do none of this,
​tell Me of your needs.’”

Indeed! What a deep sense here of what we call “petitionary prayer.” For too many of us In the theistic traditions prayer is often simply an attempt to persuade God to do something for us. Prayer is asking God for this or that. The author of this treatise thoroughly understands that, but in trying to lead us to the “deeper stuff,” contemplative prayer, he is wise in not just ignoring or throwing out or minimizing the role of petitionary prayer in the lives of most people. Actually this kind of simple prayer is a good starting point for Prayer of the Heart. God takes us and loves us and is with us exactly where we are. So never pooh-pooh a simple person’s simple prayer. That prayer in which we tell God of our needs is not for the sake of persuading God to help us(or someone we care about) but to simply abide in the Presence, and so it becomes a gateway to the true Prayer of the Heart. And true Prayer of the Heart is perhaps best understood as the Christian/Sufi experience of advaita, true non-dualism–expressed this way, however, itsounds like just another abstract idea or notion. Our author expresses it in a much more beautiful and profound way:
“In the silent niche of the heart the lover experiences the truth that there is only one prayer that underlies all of creation–the prayer in which the Beloved is present, not as a personal God or Creator, but as something both inexpressible and intimate. In this innermost recognition of the heart the lover recognizes the Beloved as something inseparable from himself. And in these moments of absorption only the Beloved exists. This primal awareness of the heart is the foundation of all prayer and all praise. In the words of Rumi: ‘Become silent and go by way of silence toward nonexistence, and when you become nonexistent you will be all praise and laud.’ Through the prayer of the heart the lover inwardly opens to the silence of the soul where the Beloved is always present. Here the lover and the Beloved meet, and the lover surrenders into the emptiness. In the formlessness of love we are absorbed deeper and deeper until we are so lost that there is only the ecstasy of unknowing. The anonymous author of The Cloud of Unknowing describes this as the ‘highest part of contemplation’ which ‘hangeth all wholly in this darkness and in this cloud of unknowing; with a loving striving and a blind beholding unto the naked being of God Himself only.’”

Let us now leave the ambience of this marvelous little book and move in a different direction. Earlier I mentioned that I am not in favor of a language that inclines toward a methodical, step-by-step approach to Prayer of the Heart. There’s a reason for that, and here I would like to invoke some Gospel language and imagery, specifically Luke 23: 39-43, very appropriate considering we are in the season of the remembrance of the death and resurrection of Christ. Let me quote:
“One of the criminals who were hanged railed at Jesus, saying, ‘Are you not the Christ? Save yourself and us.’ But the other rebuked him, saying, ‘Do you not fear God, since you are under the same sentence of condemnation? And we indeed justly; for we are receiving the due reward of our deeds; but this man has done nothing wrong.’ And he said, ‘Jesus, remember me when you come into your kingdom.’ And he said to him, ‘Truly I say to you today you will be with me in Paradise.’”
First of all note the radical change taking place as the text proceeds. We begin in a world we know quite well–the world of rewards and punishments, of man-made law and order, of strict measure and intense self-regard. Where we end up is way beyond all this, in a transcendent place of “unspeakable delineation.” Two criminals are executed, each on a cross, alongside Jesus. In a sense they are getting “what they deserve”–according to man-made law. These guys were “bad to the bone” because even then execution was not usually done for petty crimes. But no matter the nature of their criminality; the Gospel does not focus on their “badness.” It merely points at this label that they were given then–for indeed we are prone to live by labels, like also “goodness,” “holiness,” etc. For Jesus himself said that ONLY God is good, only God is holy.
It appears that both criminals are somehow aware of the charges against Jesus: that he claims he is “the Christ” and the “Son of God” and that he has some kind of kingdom that cannot be touched by the Jewish and Roman authorities. One criminal urges him with words that echo and remind one of the Devil’s temptation of Jesus in the desert: “Save yourself (and us)” –earlier in Luke the Devil tells Jesus that if he is the Son of God to throw himself off the heights and he won’t be hurt–meaning his divine nature will save him from all harm (Lk4: 9-13). That criminal is making that kind of statement to Jesus and including himself in it. Very clever. It is that continual and perennial offer of a false identity to all of us; it is the distortion of our own divine nature.
The other criminal acknowledges the “rules of the game”–he and his cohort are “guilty”–as we all are and as Kafka and the existentialists have pointed out. But even according to the “rules” of this game, Jesus is “innocent,” so something is really wrong here. The thing is that here we are in this world of “guilty” and “innocent” labels, and these can be manipulated in all kinds of ways. But this criminal somehow manages to step out of this world with one heart-rending expression: “Remember me when you come into your kingdom”–whatever that kingdom is, it surely must be better that this! Here let us recall that Sufi invitation to Prayer at the beginning of this reflection: “…if you do none of this, then tell Me of your needs.” This criminal has uttered the quintessential prayer of petition! And this is the real and true gateway to the Prayer of the Heart. And when we stand with this criminal and utter from our own depths this kind of prayer of petition than we are on the way to this Prayer.
Now note the response of Jesus. There is an immediacy here that is breath-taking–“Today”, not an evaluation of the merits of the man, not an invitation to be “polished” and “prepared” in some afterlife purgatory that later theological and spiritual reflection seemed to need for “purification” purposes–I never could understand that. That person on the cross is not in a position to proceed toward God step-by-step in a well-organized spiritual life following all the religious rules of his day. No, with that cry he is more like catapulted into the Divine Reality, or perhaps it would be more accurate to say that his heart and his awareness are suddenly opened up to who he really is. That’s why I think that this figure of Good Friday, Jesus on the Cross, is the most radical and deepest koan of all–the one that shatters our self-constructed walls and puts us in Paradise.
So, Jesus tells him: “Today you will be with me in Paradise.” The word “paradise” is extremely complex and rich in meaning. Avoiding the silly, the superficial, the cliché, the narrow readings of this word, what it refers to is that unspeakable intimacy with God. “Paradise” is where we are one with God; we “walk with Him as with a friend”–as Genesis refers to it in its mythic presentation of human origins. This is the Christian (and Judaic and Islamic ) meaning also in its mystical traditions, and also one could claim that this Is the Western equivalent of the Advaita of the Upanishads and Shankara and Kashmir Saivism. But be that as it may, truly it is the proper Scriptural symbol for what it means to be in continual Prayer of the Heart. And this is not some kind of “mystical option” but what it truly means to be a Christian and even simply a human being. Dostoyevsky’s archetypal Russian monk, Father Zosima said that if we had the eyes to see it, we would see that indeed “Today we are in Paradise.”