He is best known for his short work, published in 1892, Der sogenannte historische Jesus und der geschichtliche, biblische Christus (The so-called historical Jesus and the historic, biblical Christ).
Kähler was born in Neuhausen (now Guryevsky District) near Königsberg and died in Freudenstadt.
He had a profound impact upon the famous Protestant theologian, Paul Tillich.
The gospels serve as our only sources, and they are limited in scope, leaving many unanswered questions.
One must resist the urge to speculate too much about the life of Jesus, as some historical analogies and psychoanalyses do.