 The Early Church, he argued, was ruled not by legal concepts but by a power he called "charisma" (from the Greek 'charis'), which is "a gift of grace" bestowed by the Holy Spirit.In his work Sohm explored how the charismatically based Jesus movement of the Early Church changed into the legalistic bureaucracy of Roman Catholicism.The sociologist Max Weber derived his concept 'charismatic authority' from Sohm's 'charismatic organization,' a term Sohm had coined in "Kirchenrecht" to describe the social organization of primitive Christianity.