This phrase, which is disappearing, is equivalent to a caution to snakes.
1833. The way he fights is a sin to Crockett.Sketches of D. Crockett, p. 30 (N.Y.).
1835. Well now the way that ar cotton goes, is a sin to Crockett!Ingraham, The South-West, i. 140.
1838. Ay, ay, sir; its a sin to Moses, such a trade [as mine is, said the stoker].E. Flagg, The Far West, i. 71.
1848. The way she gulped arterwards, and stared, and twisted her fishy mouth, was a sin to Davy Crockett.W. E. Burton, Waggeries, p. 22 (Phila.).
1853. There was fifes and fiddles, brass horns and everything, and the way they puffed their jaws and worked their arms was no sin to Moses.A Hoosier at a Fancy Ball: Daily Herald, St. Louis, May 20.
1861. The way some of your city wags stuff our honest clodhoppers is a sin to Moses.Oregon Argus, March 23.