I’m posting this extract from Metropolitan Kallistos’ booklet as I wanted to have a resource online that I can refer people to – for reasons that will probably become clear in the following post and a new page.

‘In my beginning is my end.’ The purpose of prayer can be summarized in the phrase, ‘Become what you are’. Become, consciously and actively, what you already are potentially and secretly, by virtue of your creation according to the divine image and your re-creation at Baptism. Become what you are: more exactly, return into yourself; discover him who is yours already, listen to him who never ceases to speak within you; possess him who even now possesses you. Such is God’s message to anyone who wants to pray: ‘You would not seek me unless you had already found me.’

But how are we to start? How, after entering our room and closing the door, are we to begin to pray, not just by repeating words from books, but by offering inner prayer, the living prayer of creative stillness? How can we learn to stop talking and to start listening? Instead of simply speaking to God, how can we make our own the prayer in which God speaks to us? How shall we pass from prayer expressed in words to prayer of silence, from ‘strenuous’ to ‘self-acting’ prayer (to use Bishop Theophan’s terminology), from ‘my’ prayer to the prayer of Christ in me?

One way to embark on this journey inwards is through the Invocation of the Name.

Lord Jesus . . .

It is not, of course, the only way. No authentic relationship between persons can exist without mutual freedom and spontaneity, and this is true in particular of inner prayer. There are no fixed and unvarying rules, necessarily imposed on all who seek to pray; and equally there is no mechanical technique, whether physical or mental, which can compel God to manifest his presence. His grace is conferred always as a free gift, and cannot be gained automatically by any method or technique. The encounter between God and man in the kingdom of the heart is therefore marked by an inexhaustible variety of patterns. There are spiritual masters in the Orthodox Church who say little or nothing about the Jesus Prayer. But, even if it enjoys no exclusive monopoly in the field of inner prayer, the Jesus Prayer has become for innumerable Eastern Christians over the centuries the standard path, the royal highway. And not for Eastern Christians only: in the meeting between Orthodoxy and the West which has occurred over the past seventy years, probably no element of the Orthodox heritage has aroused such intense interest as the Jesus Prayer, and no single book has exercised a wider appeal than The Way of a Pilgrim. …

The Invocation of the Name is a prayer of the utmost simplicity, accessible to every Christian, but it leads at the same time to the deepest mysteries of contemplation. Anyone proposing to say the Jesus Prayer for lengthy periods of time each day – and, still more, anyone intending to use breathing control and other physical exercises in conjunction with the Prayer – undoubtedly stands in need of a starets, of an experienced spiritual guide. Such guides are extremely rare in our day. But those who have no personal contact with a starets may still practise the Prayer without any fear, so long as they do so only for limited periods – initially, for no more than ten or fifteen minutes at a time – and so long as they make no attempt to interfere with the body’s natural rhythms.

No specialized knowledge or training is required before commencing the Jesus Prayer. To the beginner it is sufficient to say: Simply begin. ‘In order to walk one must take a first step; in order to swim one must throw oneself into the water. It is the same with the Invocation of the Name. Begin to pronounce it with adoration and love. Cling to it. Repeat it. Do not think htat you are invoking the Name; think only of Jesus himself. Say his Name slowly, softly and quietly.’ [quoting Fr Lev Gillet]

The outward form of the prayer is easily learnt. Basically it consists of the words ‘Lord Jesus Christ, Son of God, have mercy on me.’ There is, however, no strict uniformity. We can say ‘. . . have mercy on us’, instead of ‘on me’. The verbal formula can be shortened: ‘Lord Jesus Christ, have mercy on me’, or ‘Lord Jesus’, or even ‘Jesus’ alone, although this last is less common. Alternatively, the form of words may be extended by adding ‘a sinner’ at the end, thus underlining the penitential aspect. We can say, recalling Peter’s confession on the road to Caesarea Philippi, ‘. . . Son of the living God . . .’. Sometimes an invocation of the Mother of God or the saints is inserted. The one essential and unvarying element is the inclusion of the divine Name ‘Jesus’. Each is free to discover through personal experience the particular form of words which answers most closely to his or her needs. The precise formula employed can of course be varied from time to time, so long as this is not done too often: for, as St Gregory of Sinai warns, ‘Trees which are repeatedly transplanted do not grow roots.’

Kallistos Ware. The Power of the Name – The Jesus Prayer in Orthodox Spirituality – Fairacres Publ 43, (SLG Press, 1974 [1986]) 3-5.