Death in Holy Orders by P. D. James

When the body of a student of an Anglican theological college is found on the shore of a desolate stretch of coast smothered by a fall of sand, his wealthy father demands that Scotland Yard re-examine the verdict of accidental death. Commander Dalgliesh has visited St Anselm's in his boyhood and, as he is due for a holiday, agrees to pay a visit. He finds himself embroiled in one of the most puzzling cases of his career.