Thanks for the link. Unfortunately I keep getting a message saying that I have exceeded the viewing limit or words to that effect, so I can't read it! Morison seems to be fond the word absurd as according to a word search of the eBook (a facility which I was able to access) he used it 11 times in the book!
I dug out my paperback copy of the book I have (1972 reprint version) and this starts at page 9* (there is a preface and index before this) and the reference to the absurd cult appears on page 10. Here Morison is referring to the German critics who came to prominence in the late 1800's and denied the historical Jesus, but whose thinking has since ceased to carry weight**.
*The link places the quote on page 7 of the eBook.
**This is backed up by this reference: https://www.quora.com/Do-modern-hist...-Jesus-existed
So basically nothing to get excited about I think.