E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Shakespeare says, Do you smell a fault? (King Lear, i. 1); and Iago says to Othello, One may smell in this a will most rank. Probably the smell of dogs may have something to do with such phrases, but St. Jerome furnishes even a better source. He says that St. Hilarion had the gift of knowing what sins or vices anyone was inclined to by simply smelling either the person or his garments; and by the same faculty he could discern good feelings and virtuous propensities. (Life of Hilarion,A.D. 390.)