From his book, His Life is Mine, chapter #14

The incarnation of Christ was the greatest revelation of the essence of God, as well as of our own essence. If God became flesh, then we also had the potential of becoming sons/daughters of God. Yet it is through prayer that revelation takes place within our own hearts, as we move beyond the conceptual level to build a personal relationship with the person of Christ.
Prayer warms and rejoices us. It is the channel through which we receive revelation from on high.
To grasp the power of the Jesus prayer, Sophrony fist talks about the meaning of names in the Orthodox tradition.
God, he tells us, “reveals himself to the reasonable beings created by him under a plurality of names…” He gives examples: Almighty, Righteous Savior, Redeemer, Light, Wisdom, Beauty…
Invoking his name isn’t simply a means for clarifying whom we are addressing or catching his attention. It is one of the manifestations of the essence of a person.
The Name of Jesus as his Proper Name is ontologically connected with him. For us it is the bridge between ourselves and him. It is the channel through which divine strength comes to us.
He reminds us that all the sacraments of the church are accomplished by calling on his name. If you disregard “the ontological character of the Divine Names,” Sophrony writes, “…prayer and the sacraments themselves, lose their eternal reality.”
When I was a child, I wished that I had a magic bottle to rub to make the genie appear. It amused me to think of the 3 most important things I would ask from this genie. In the case of the Jesus prayer, we should be careful not to confuse the invocation of Jesus’ name with magic. Repetition of his name does not automatically bestow supernatural powers. Instead, it enables a mystical and personal union with Christ. when it is uttered “as a true confession of faith…with love, reverence, and fear.“
Sophrony elucidates the mystical experience of the Jesus prayer, through the parallel of two people in love. Imagine yourself whispering the name of a beloved repeatedly or gently addressing the person by name. Each invocation, filled with love and tenderness, increases the feeling of intimacy and love in your heart and evokes fresh dimensions of the beloved person. This is the case with the Jesus prayer. Each time we invoke his name with love, we feel more deeply connected with him, “his likeliness becomes ever more precious, and happiness makes us notice new traits all the time.”
“The most important thing to ask in prayer,” Sophrony counsels, is the “the union of our whole being with God.”
This is why the Jesus prayer is called prayer of the heart. It enables us to transfer the knowledge of Christ from the head to the heart and to connect with him on a personal, individual level, thus experiencing eternity.
He reminds us again that there is nothing automatic or magic about the Jesus prayer. If we don’t keep the commandments, for example, our prayer is in vain. Most importantly we have to address the person of Christ and love him.
It is not enough to pronounce the sound of the human word, which alters with the language used. It is essential to love him whom we invoke.
Achieving this mystical union does not simply make us serene. It transforms us.
Love toward Christ filling the whole man, works a radical change in man
The character of Christ is revealed to us through the experience of intimacy with him. And through this intimate union we encounter the “perfect light in which there is no darkness.”