- St Albert the Great - Cleaving to God
Attributed to the teacher of St Thomas Aquinas, but in any case, a well-loved tract.
- St Alphonsus de Liguori - Uniformity With God's Will
A short work but contains the secret to the highest sanctity.
- St Augustine - Enchiridion on Faith, Hope and Charity
St Augustine "was a marvelous example to pastors in his intrepid defense of the true faith, and ... was likewise the genius who constructed a philosophy that can truly be called Christian because of its harmony with the faith, and a tireless promoter of spiritual and religious perfection". - John Paul II
- St Augustine - On Christian Doctrine
Written to guide the reader in the understanding and interpretation of the Sacred Scriptures, according to the analogy of faith.
- St Bernard of Clairvaux - On Loving God
His writings "seem to have been nourished with the breath of the Divine Spirit, and to shine with a light so bright, that the course of the centuries cannot quench it; for it shines forth from the soul of a writer thirsting after truth and love, and yearning to nourish others and to make them like to himself" - Pope Pius X11
- St Bonaventure - The Mind's Road to God
The work outlines a vigorous intellectual journey which leads to the threshold of contemplation where "all intellectual operations should be abandoned, and the whole height of our affection should be transferred and transformed into God."(Ch 7)
- St Catherine of Siena - Dialogue
Paul VI, proclaiming her Doctor of the Church, said: "what is most striking in the saint is the inherent wisdom, the lucid, profound and inebriating assimilation of divine truths and of the mysteries of the faith... "
- St Catherine of Genoa - Treatise on Purgatory
When about twenty-six years old she became the subject of one of the most extraordinary operations of God in the human soul of which we have record.
- De Caussade - Abandonment to Divine Providence
The " Treatise " comprises two different aspects of Abandonment to Divine Providence; one as a virtue, common and necessary to all Christians, the other as a state, proper to souls who have made a special practice of abandonment to the holy will of God.
- St Francis de Sales - Introduction to the Devout Life
The "Introduction" is recognized as a masterpiece of mystical and devotional literature. Written by a Doctor of the Church for laity interested in living a better life, it urges upon all men and women a hatred of sin, detachment for the things of the world, love of God and constancy in prayer.
- St Francis de Sales - Treatise On the Love of God
Written to bring souls to a deeper knowledge and appreciation of the love of God, the "Treatise" is a work of genius in devotional dogmatic theology. Spiritual instruction of the highest order.
- Garrigou-Lagrange, Reginald - Life Everlasting
Written by a famous theologian in simple language, this is a discussion in 32 articles of the Four Last Things- Death, Judgement, Heaven and Hell. If you are looking for something to wake you up spiritually, this could be it!
- Garrigou-Lagrange, Reginald - The Three Ages of the Interior Life
The summary of a course on ascetical and mystical theology given for over twenty years at the Angelicum in Rome.
- Grou, John Nicholas - Spiritual Maxims
Maxims for practising the interior life.
- Blessed Henry Suso - A Little Book of Eternal Wisdom
For over five hundred years it has enjoyed undiminished popularity, as at once a religious and literary masterpiece.
- St John of the Cross - Ascent of Mount Carmel
"It is not going too far to liken the place taken by St. John of the Cross in mystical theology to that of St. Thomas in dogmatic" - E. Allison Peers
- St John of the Cross - Dark Night
Describes the soul's conduct along the spiritual road which leads to the perfect union of the soul with God through love as far as is attainable in this life.
- St John of the Cross - Spiritual Canticle
St. John of the Cross, according to his commentary, sings in this poem about the loving exchange between a soul and Christ, the Bridegroom.
- John of Rusybroeck - The Adornment of the Spiritual Marriage
About the loving exchange between a soul and Christ, the Bridegroom.
- Bro. Lawrence - The Practice of the Presence of God
Brother Lawrence simply and beautifully explains how to continually walk with God
- Ven. Louis of Granada - The Sinner's Guide
St. Teresa of Avila stated that this work of Venerable Louis converted over 1,000,000 souls in her day. She, along with St. John of the Cross, St. Francis de Sales, St. Charles Borromeo, St. Vincent de Paul, and St. Rose of Lima, all counted it among their favorite spiritual books.
- St Louis Marie Grignion de Montfort - True Devotion to the Blessed Virgin
A classic on devotion to Mary.
- St Teresa of Avila - Interior Castle
A vivid, readable description of the stages in mystical prayer from a Doctor of the Church.
- Thomas a Kempis - The Imitation of Christ
This is a classic of spiritual writing that has had more print editions than any book after the Bible. It is arranged in an ideal format for reading online.
- St Alphonsus de Liguori - The Great Means of Salvation and Perfection
I do not think that I have written a more useful work than the present, in which I speak of prayer as a necessary and certain means of obtaining salvation, and all the graces that we require for that object. If it were in my power, I would distribute a copy of it to every Catholic in the world, in order to show him the absolute necessity of prayer for salvation." - St Alphonsus in the Introduction. (My emphasis - Ed)