selective blur on a street sign indicating martin luther platz square, one of the main squares of dusseldorf city center in

reformation reformist martin luther platz square dusseldorf duesseldorf german germany deutsche deutschland deutsch sign street lutherian lutherianism protestant religion religious roadsign city center avenue urban architecture nrw old town destination altstadt landmark signage road cityscape downtown travel north rhinewestphalia europe theology christian protestantism selective blur indicating one main squares focus sign osa priest theologian author hymnwriter professor augustinian friar seminal figure followers lutherans ordained priesthood 1507