In the Introduction to Pastor John's 1979 monograph, Love Your Enemies, he confesses his concern about the hard work of academic reading. He writes:
Every scholarly work on the New Testament is preponderantly an intellectual exercise. The work of thinking which the production of a book like this demands from the author is demanded also from its reader. But because of the nature of the reality with which this work has to do, the necessary preponderance of intellectual work can nevertheless frustrate the goal for which the work is done.
For that reality is and demands far more than thinking. Adolf Schlatter has warned: "Thought can become scholasticism, a mere jangle of words, if the concept replaces the essence, or dogma replaces reality." The reality from which Jesus' command of enemy love springs and the reality at which it aims is not exhausted by correct thinking about the command.
If a book about this command does not ultimately lead beyond mere thinking to an active realization of what the command intends, then that thinking itself, in all its possible technical accuracy, becomes worthless. "Though I understand all mysteries and all knowledge . . . and have not love, I am nothing."
'Love Your Enemies:' Jesus' Love Command in the Synoptic Gospels and the Early Christian Paranesis, a history of the tradition and interpretation of its uses, SNTS, 38, (Cambridge: Cambridge University Press, 1979), 3, paragraphing mine.