The article consists of two parts and is devoted to the formation of a new bourgeois ethic within the late Medieval mentality. This process is studied on the material of the creation of the so-called “small preachers”, whose activities unfolded in Germany in the 1st half of the 14th century. In the first part, the personalities of the preachers themselves (16 names) are considered, in the second part their teaching, taken in an integral form, is analyzed. This teaching is based on Neoplatonic emanationism. God, present in a person as a “spark”, reveals himself through actions, so that a person becomes attached to God’s actions as an instrument. This is what the “auto-determination” of a person taken out of the control of ecclesiastical and secular institutions looks like. At the end of the article, an attempt is made to re-read M. Weber’s famous book The Protestant ethic and the spirit of capitalism. After all, in his work Weber identified only the social manifestations of these mental dynamics. It is only through this internal dynamic that the external manifestations identified by M. Weber receive their ultimate justification. Without this underpinning, these manifestations remain little more than witty observations and have no binding character.