The Inward Temple. There is no need to weep much over the destruction of a church; after all, each of us, according to God's mercy, has or should have his own church—the heart; go in there and pray, as much as you have strength and time. If this church is not well made and is abandoned (without inward prayer), then the visible church will be of little benefit.
—Archbishop Barlaam to Abbess M., Russia's Catacomb Saints, p. 281
Also, it is absolutely essential that every Orthodox Christian go beyond the use of the prayer books listed below and cultivate an interior life of the heart through the use of the Jesus Prayer ("Lord Jesus Christ, Son of God, have mercy on me"). Ideally, this should be done under the guidance of a spiritual father or mother. The practice of the Jesus Prayer is central to Orthodox spirituality. For an introduction to this—set in the broader context of the Orthodox understanding of salvation as purification, illumination, and glorification—see especially (among the books listed above) the work by Metropolitan Ierotheos (Vlachos) entitled Orthodox Spirituality. One should also read the Russian Orthodox classic, The Way of the Pilgrim. Another work widely acknowledged as an outstanding "handbook" on the Jesus Prayer is The Art of Prayer (Faber & Faber; now back in print). Here is an excerpt from that classic work:
"There are many among you who have no knowledge of the inner work required of the man who would hold God in remembrance. Nor do such people even understand what remembrance of God means, or know anything about spiritual prayer, for they imagine that the only right way of praying is to use such prayers as are to be found in Church books. As for secret communion with God in the heart, they know nothing of this, nor of the profit that comes from it, nor do they ever taste its spiritual sweetness. Those who only hear about spiritual meditation and prayer and have no direct knowledge of it are like men blind from birth, who hear about the sunshine without ever knowing what it really is. Through this ignorance they lose many spiritual blessings, and are slow in arriving at the virtues which make for the fulfilment of God's good pleasure." (p. 43)For a sampling of spiritual treasure from this book read this collection from the letters of St. Theophan the Recluse, whose writings comprise a large portion of The Art of Prayer.
Finally, though the many-volumed Philokalia is the main corpus of writings on the hesychastic tradition, it is normally advised that a person who wishes to read this first immerse himself or herself in the Lives of the Saints. These typically comprise the "grade school" instruction—to see how others have embraced these practices and become glorified—, although as Father Seraphim Rose of Platina noted in his Introduction to Blessed Paisius Velichkovsky, many aspects of any given Saint's Life are not to be specifically emulated. (One should definitely read his very instructive introduction.) Then one can move on to "high school," reading and applying to their life—and hopefully under a wise spiritual guide—the principles contained in the major preparatory text for the Philokalia: the Evergetinos (The Center for Traditionalist Orthodox Studies, multi-volumed).
Comboschini (The Prayer Rope): Meditations of a Monk of the Holy Mountain Athos. This is an excellent introduction to the practice of the Jesus Prayer.
Introduction to the Jesus Prayer, by Her Royal Highness, Princess Ileana of Romania (later, Mother Alexandra, Abbess of the Orthodox Monastery of the Transfiguration in Ellwood City, PA).
Prayer of the Heart for the Faithful Living in the World, by Elder Joseph of Vatopaidi (Spiritual Child of Elder Joseph the Hesychast).
Father Paisios the Athonite: Guidance about the Jesus Prayer. An excerpt from With Elder Porphyrios: A Spiritual Child Remembers, by Constantine Yiannitsiotis.
Interpretation of the Prayer - Lord, have Mercy!. An excerpt from the fifth volume of the Philokalia (not yet published).
Elder Joseph the Hesychast and the Teaching of Mental Prayer Which Flowed from His Letters. A homily by Abbot Ephraim of Vatopaidi Monastery.
Concerning the Jesus Prayer. From the Jordanville Prayer Book (1996 ed).
On Practicing the Jesus Prayer, by St. Ignaty (Brianchaninov)
On Prayer of the Heart: Excerpts from Exploring the Inner Universe, by Fr. Roman Braga.
An Orthodox Prayerbook, a handy compilation of Orthodox prayers from the website of the Greek Orthodox Church of the Transfiguration in Lowell, MA.
Prayerbook of Holy Trinity Monastery: The entire text of this excellent prayerbook!
An Aid to Prayer: Some Thoughts on the Use of a Prayer Book. From the Orthodox America website.
Order of Prayer and Worship for Orthodox Faithful. Talk Given by Fr. John Townsend at the 1998 Southern Orthodox Conference, Atlanta, Georgia.
Explanation of the Lord's Prayer: An Excerpt from Concerning Frequent Communion, by Saint Nikodemos the Hagiorite.
The Lord's Prayer: A Homily by Archimandrite George, Abbot of the Holy Monastery of St. Gregoriou, Mount Athos. Available in four Languages!
"All I Can Do Is Pray". From The Veil, Vol. 13, No. 1.
On Prayer, excerpts on a variety of issues related to prayer, from the Letters of St. Theophan the Recluse.
A Prayer Rule, an excerpt from The Spiritual Life and How to Be Attuned to It, by St. Theophan. See also by the same author: Inner Peace.
The Cell Rule of Five Hundred of the Optina Monastery: another prayer rule to consider adapting to your abilities and circumstances. I posted this mainly because of the example it provides in the meshing of fixed prayers and Jesus Prayers.
Selections from The Arena, On Prayer: by St. Ignaty (Brianchaninov)
The Power of the Jesus Prayer. Based on the Testimony of the Nun Tatiana (1912). "If someone dies while saying the Jesus Prayer, his soul stands in the presence of the Lord, and he will be inseparable from Him for eternity. Likewise, if a man dies while uttering the prayer, 'Most Holy Theotokos, save me, a sinner,' then he will be inseparable from the Mother of God. If someone is not able to utter even a single word, then, if he struggled to attain this prayer during his life on earth, his soul will say it for him on his deathbed. The state in which the soul leaves the body is the state in which it abides forever. There will be no change for the better. Only if one is commemorated (on earth) can he alter the state of his soul."
Humble-Mindedness: The Doorway to Pure Prayer: An interview with Elder Dionysius (Ignat) of the St. George Kellion, Kolitsou Skete, Mount Athos, Greece. From The Orthodox Word (Jan-Feb, 2005).
Prayer: Corporate and Private, from the book Marriage and the Christian Home
The Icon Corner, from the book Marriage and the Christian Home
Orthodox Prayers, including almost the entire Lenten Triodion (though a different version than the famous one produced by Bishop Kallistos and Mother Maria).
How to Set Up a Personal Commemoration Book, for personal use at home. By Fr. John Whiteford.
Prayer With the Non-Orthodox: a Q&A from Orthodox Tradition, vol. XIV, no. 4. Deals especially with the problem of praying at meals with heterodox Christians.
Praying for the Non-Orthodox, from Orthodox Life.
Prayer Life in an Orthodox Home, by Archpriest Roman Lukianov.
Prayer, Feasts, and Fasts, by the Ever-Memorable Metropolitan Philaret of New York.
The Psalms of David. Chapter Two from "The Typicon of the Orthodox Church's Divine Services."
On the Necessity of Constant Prayer for all Christians in General, by St. Nikodemos of the Holy Mountain.
On Watchfulness, Prayer and Confession: A Homily by Elder Ephraim of Philotheou. Translated from the Greek by Fr. Seraphim Bell.
