Adrienne von Speyr begins her longest and deepest book on prayer, The World of Prayer [Die Welt des Gebetes], by anchoring the original source of prayer in the eternal dialogue exchange of the Father, Son, and Holy Spirit. Her insight is an original and fruitful contribution that has yet to be realized in Christian reflection on prayer. It is an idea that once realized makes perfect and profound sense. As far as I know, as a theologian, this idea has never been said with this much clarity and depth.
Each person of the Trinity relates to the other in an attitude of prayer. The Son looks to the Father in that attitude of expectation and fulfillment that characterizes prayer. The Son beholds the Father in love, trust, and expectation. The Father responds with beholding, love, and fulfillment. The Holy Spirit wraps all of this eternal dialogue of exchange with the divine fire of his love while also being the eternally spirated fruit of this prayerful contemplation and action. The prayerful aspects of worship, petition, and decision are also present in the loving exchange between the Father, Son, and Holy Spirit. This first section of the book makes one realize the dynamic relations in the one God who is Trinity.
Adrienne then moves to discussing the prayer of Adam and Eve before and after the Fall. The prayerful intimacy with God in Paradise is recognized by Adam and Eve simply as walking with God in the Garden. After the Fall, the realm of prayer is characterized by distance and longing ("De profundis", Ps 130:1) to behold once more the face of God.
With the Incarnation, creation is brought through Christ's work of redemption into his triune intimacy with the Father and Holy Spirit. He breathes on us the Holy Spirit enabling us to pray the prayer he taught us, the Our Father.
Adrienne also offers Mary as a source for understanding prayer. At each stage in Mary's life, which was lived so closely to her son, the Son of God, we are taken into the simplicity of praying to God with transparency, "I know not man" (Lk 1:34), and obedience, "be it done unto me" (Lk 1:38). We learn that authentic prayer is letting our subjective word be taken over by the Lord's objective Word.
The book could stop here, but it keeps offering more and more profound insights. Adrienne examines the growth of prayer, prayer in the different vocations, or states, of life, three kinds of prayer, direct and indirect prayer, prayer as standing before the face of God, the relation of nature and grace in prayer, and the love and fruit of prayer.
When reading this rich book on prayer life, one should know that Adrienne dictated it from within a mystical state of prayer. So it is a book on prayer written in prayer; therefore, it is best read in prayer. I can think of no book on prayer better than this one. Accessible to the beginner and profoundly deep for the advanced, I heartily, and urgently, recommend it.
You can find the book here
My review presented above was offered in another forum and is offered here as further encouragement to you to read more Adrienne