Although they never met in person, the two young saints Thérèse of Lisieux (1873-1897) and Elizabeth of the Trinity (1880-1906) nevertheless share many common elements: the same homeland, the same historical period, and the same vocation to Carmel. It was precisely these common characteristics that allowed the young Elizabeth to become acquainted with Thérèse's writings even before entering the Carmelite convent in Dijon. A comparison between the two saints, which arises spontaneously, thus finds a solid foundation, so much so that the well-known theologian Hans Urs von Balthasar wrote in the Preface to his book Sisters in spirit: Thérèse of Lisieux and Elizabeth of Dijon: “One must not judge and contrast missions which, although different, all spring from the same center [...]. However, they can be compared [...]; from such encounters, spiritualia spiritualibus comparantes, pleasant surprises and unexpected fruits arise.” Being a Seminar, we will focus almost entirely on the sources: that is, the writings of the two saints, as well as the testimonies given in the Ordinary Process and the Apostolic Process of the two saints. Phenomenological and hermeneutical approaches will therefore be essential, incorporated into an inductive-deductive method applied to the sources. The joint analysis and dialogue on the writings of the two saints will lead students to sharpen their theological-spiritual interpretation skills of some classic writings on spirituality, such as those of the two saints in question.