The discussion about Bach's music here goes beyond the usual lecture: organ compositions are examined through theological meanings, numerical symbolism, and the history of interpretations. Alexander Fiseisky combines research depth with lively explanation, helping to hear new connections and internal logic in familiar pages. Bach's music often seems impeccably structured, almost mathematically precise, but behind this clarity lies a vast world of meanings. In this meeting, we will talk about how Bach's organ works are connected to events in Sacred History, the choral tradition, and a system of symbols that opens up to the attentive performer and listener. The lecture-seminar format is especially valuable in that here not only the narrative matters, but also the very process of reflection, as the musical text gradually reveals itself as a complex and living statement. At the center of the seminar is the experience of interpreting Bach's organ compositions in the context of the ideas of A. Schweitzer, B. L. Yavorsky, and F. Smenda. These researchers approached the composer's legacy in different ways, but it is precisely the comparison of their views that helps the modern musician to understand more accurately the structure of Bach's music, its imagery, and internal dramaturgy. For the listener, this is especially interesting because familiar works begin to be perceived not as abstract examples of ancient academic music, but as texts in which theological, symbolic, and emotional layers are encoded. The seminar leader Alexander Fiseisky is known as a performer and educator who works deeply with the organ repertoire. Therefore, the conversation promises to be substantial and at the same time accessible. Here, dry theory is not important, but the attempt to show how the choral melody, numerical symbolism, structure of form, and spiritual experience of the era connect in one work. This approach helps to better understand why Bach's organ opuses had such a strong impact on his contemporaries and continue to hold attention centuries later.