From 1837 to 1857, Johann Hinrich Wichern, founder of the Rauhe Haus and the Inner Mission, traveled all over Germany. He campaigned for the Rauhe Haus in Hamburg and the attached Brüderanstalt, initiated the establishment of rescue houses, inspected prisons, made the cause of the Inner Mission known as a reform project for Germany and built up a large network of people and institutions. On the way he wrote regularly to his wife Amanda to let her share in what he was experiencing, but also to record experiences, insights and encounters in a kind of diary for himself. Amanda Wichern kept in touch with her husband through letters. The letters are a powerful piece of contemporary history. They open up multifaceted and pointed insights into Johann Hinrich and Amanda Wichern's thinking and work. Wichern's character is more evident in the letters to his wife than in his writings. Amanda Wichern's personality comes into focus and her importance for Wichern's wide-ranging commitment becomes tangible. The relationship between Johann Hinrich Wichern and his wife Amanda takes shape. These letters are being published on the 175th anniversary of Diakonie in Germany and the 190th anniversary of the founding of the Rauhe Haus in Hamburg. The letters contribute to a better understanding of the origins of diakonia and at the same time offer impulses in view of current crisis phenomena and transformation processes.