Gabriel Marcel endeavors to expound his view of philosophy from Existential Phenomenology through Metaphysics to Spirituality. Yet, no matter how explicit he is in explaining about his Phenomenology and Metaphysics, he still remains only implicit in his way of figuring out his thoughts on Spirituality. This last gap may apparently be fulfilled through a certain dialogue between Marcel and Saint Theresa of Lisieux who in her “Way of Spiritual Infancy” may serve as a spring-board in cementing the hole within the panorama of Marcel’s philosophical system. Theresa’s proposal of an absolute trust in the Lord, together with the aim of mystical love, as well as purgation in place of extraordinary experiences, may highlight for us the doctrine of Faith, Hope, and Love already embedded in Marcel’s philosophical thinking. In addition, the dialogue between the two persons especially emphasizes the intersubjectivity leading from human persons to the Holy Trinity that forms a perfect community as a mode for all families.