This 1963 text offers a critical reflection on Bonhoeffer's concept of the "non-religious person of the adult world." The author, Ladislav Hejdánek, challenges the metaphor of adulthood as a simple developmental stage following childhood, arguing that such a view fails to capture the radical essence of the modern era. According to Hejdánek, the core of modernity lies not in the mere maturation of humanity but in a fundamental shift in the perception of time and history. While earlier generations perceived the past as something standing before them, guiding their path while the future remained hidden behind their backs, the modern individual has undergone a 180-degree turn. In this new paradigm, people carry their past on their backs as a weight or foundation, while directing their gaze forward into the unknown or partially known future. This ontological and epistemological shift defines the onset of the modern age and the identity of the modern human, who breaks away from traditional religious frameworks to face the uncertainty of the coming time with a sense of historical responsibility.