IN THE DAYS OF SIMON STERN by ARTHUR A. COHEN 464 pages. Random House. $8.95.
It is one of the most venerable axioms of writingcertainly as old as Moll Flanders (1722)that novels should be about sinners. Saints are difficult enough to deal with in real life, let alone in fiction.
As the author of a previous religious novel, The Carpenter Years (and non-fiction books on Martin Buber and The Natural and the Supernatural Jew), Arthur Cohen knows all the odds, creative and commercial. Yet he has taken on a saint and a fable in fiction, and won apparently by sheer moral passion.