A dictionary of Proverbs (Oxford Paperback Reference)

Every DOG has his day

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  1545 R. TAVERNER tr. Erasmus’ Adages (ed. 2) 63 A dogge hath a day. 1600-1 SHAKESPEARE Hamlet v. i. 286 Let Hercules himself do what he may, The cat will mew, and dog will have his day. 1611 R. COTGRAVE Dict. French & English s.v. Fevrier, Euerie dog hath his day. 1726 POPE Odyssey V. xxii. Dogs, ye have had your day; ye fear’d no more Ulysses vengeful from the Trojan shore. 1837 CARLYLE French Revolution III. I. i. How changed for Marat, lifted from his dark cellar!.. All dogs have their day; even rabid dogs. 1863 C. KINGSLEY Water Babies ii. Young blood must have its course, lad, And every dog his day. 1978 ‘M. CRAIG’ Were He Stranger x. ‘She could be his sister.’ ‘No way—not with a face like that.’ ‘Well, every dog deserves his day.’ ■ opportunity, taken; success
  

Every DOG is allowed one bite
The proverb is based on the old common law rule (dating at least from the seventeenth century) by which the keeper of a domestic animal was not liable for harm done by it unless he knew of its vicious propensities. Quot. 1913 explains the thinking behind this.

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  1902 V. S. LEAN Collectanea I. 439 Every dog is allowed his first bite i.e. is not punished. 1913 Spectator 15 Mar. 440 Every dog is allowed by the law one free bite. After the dog has once bitten a person it is presumed that its owner knows it to be ‘savage’. 1968 P. FOOT Politics of Harold Wilson x. In March 1967.. Wilson rounded on the Left at a Parliamentary Party meeting, warning them that ‘a dog is only allowed one bite’ and threatening them with a General Election unless they came to heel. 1980 ’A. BLAISDELL’ Consequence of Crime (1981) ii. She got arrested. ..They say every dog [is] allowed one bite. .. But it was a vice thing. .. I told her to get out. ■ reputation