No one wants to fill in the gaps, so I will.
The Author is John Buchan, the book, as Mippy guessed, is "The 39 Steps", and the character is Richard Hannay. Buchan, son of a Scottish minister (church, not political) was a politician and historian as well as fiction writer. His lifelong love of "Pilgrim's Progress" is evident in several of his books, most notably "Mr. Standfast". In 1935, Buchan was made 1st Baron Tweedsmuir in preparation for his appointment as Governor-General of Canada, which he held until his death in 1940.
"The 39 Steps" is the first book featuring Richard Hannay. A man is murdered in Hannay's apartment and Hannay, the principal suspect, flees all over England and Scotland, changing disguise in each chapter, trying to escape both the police and the spies who really killed the victim. The plot is slight, and was much mangled to make the 1935 movie, starring Robert Donat.
I liked these stories when I was growing up, and still have a fondness for them, though they really are dreadfully corny.