The isenheim altarpiece, with its gruesome details of christ's flesh wounds, originally hung in

It originally hung in  Isenheim hospital. 

The altar piece was created by the Brother of St. Anthony, St. Anthony is the patron for skin disease. The said hospital was the place where monks give their care for sick people that have skin diseases. Grünewald’s painted Christ expresses the story of heaven, earth, the sufferings, but also points for a miracle to transpire. It extends the story by involving the Saints in the scene including St. Anthony. The whole painting is an expression of human suffering, hope, and faith to the hospital's patients. This was according to the explanation in smarthistory.org.