AbstractWithin the Montessori community, it is widely accepted that a teacher’s readiness to work in a Montessori elementary school is primarily influenced by the training program they have completed. The highest-quality programs do not only provide knowledge about working with teaching materials and the principles of classroom design, but also literally transform the student’s personality, turning them into adults capable of becoming a foundational element of the environment. This assumption differs from the self-perception of novice teachers. The relevance of this study stems from the need to reveal the true nature of the teacher’s systemic role and to examine the issue of excessive emotional strain. The aim of the present research is to analyze the role of the adult, to identify the key functions, and demonstrate the significance of profound personal transformation for an effective educational environment. The methodological basis of the study consists of the principles of Maria Montessori’s pedagogy regarding the prepared educational environment and the role of the “prepared adult,” as well as her age-based periodization of child development and L. N. Gumilev’s concept of passionarity, which is used here to analyze the emotional and energetic characteristics of a teacher’s professional activity. Also of great importance is the idea of developing autonomy in the course of cosmic education (E. N. Prokofyeva, K. E. Sumnitelny, C. Grazzini, J. Shyber), as well as psychological research on the issue of self-regulation and independent decision-making (T. O. Gordeeva, V. V. Davydov, R. A. Deci, A. Murray and E. Ryan). The hypothesis was based on the assumption that genuine professional development requires continuous internal work that goes beyond the scope of methodological disciplines. The novelty of the study lies in its application of the passionarity theory to explain the emotional burden of the educator and to detail the functions of a teacher working with primary school children. Their development occurs during the transition of their minds from absorption to reasoning and the implementation of the concept of cosmic education in educational activities. The results showed that it is the adult who acts as the connecting link in the triad (child — environment — adult), performing organizational-substantive, socio-communicative, diagnostic-navigational, and spiritual-moral functions. The theoretical significance lies in affirming the educator as the bearer of a worldview, while the practical significance lies in identifying the risks of burnout due to the high dependence of educational outcomes on the teacher’s personality. We are aware of the vulnerability of a system where the class activity relies on the enthusiasm of an individual. The authors conclude that the effectiveness of the educational process depends directly on the moral maturity and energy of the educator. An environment without a well-prepared adult is lifeless; therefore, systematic efforts are needed to create a culture of professional support. This requires a deeper examination of the factors hindering the development of well-prepared adults and the development of practical ways to support educators. To this end, it is necessary to develop moral resilience and a mentorship system within the community, as well as to establish a system of mutual classroom observations by teachers and discussions of their results. It is also necessary to develop tools to help monitor professional burnout, which hinders the creation of a balance between children’s independence and the life support provided by a prepared adult.