A dictionary of Proverbs (Oxford Paperback Reference)

All’s FAIR in love and war
Cf. 1578 LYLY Euphues I. 236 Anye impietie may lawfully be committed in loue, which is lawlesse.

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  1620 T. SHELTON tr. Cervantes’ Don Quixote II. xxi. Love and warre are all one. .. It is lawfull to use sleights and stratagems to.. attaine the wished end. 1845 G. P. R. JAMES Smuggler II. iv. In love and war, every stratagem is fair, they say. 1986 S. BRETT Nice Class of Corpse xl. Then Eulalie’s eyes narrowed and she looked hard at her companion. ‘Do you believe that all is fair in love and war?’ 2002 Spectator 15 June 63 All is fair in love and war, and it is important that you sustain your marriage. You must therefore take the following, deceitful steps. "fair dealing; love; warfare
  

FAIR play’s a jewel

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  1809 W. IRVING Hist. New York II. VI. vii. The furious Risingh. in despight of that noble maxim.. that ‘fair play is a jewel’, hastened to take advantage of the hero’s fall. 1823 J. F. COOPER Pioneers II. v. Well, fair play’s a jewel. But I’ve got the lead of you, old fellow. 1935 E. F. BENSON Lucia’s Progress viii. There’s been a lil’ mistake. .. I want my lil’ rubber of Bridge. Fair play’s a jewel. 1948 L. A. G. STRONG Trevannion iv. ‘It ain’t good to win crooked.’ ‘Good for you, Stan. I agree. Fair play’s a jewel.’ "fair dealing
  

fair see also none but the BRAVE deserve the fair; a fair EXCHANGE is no robbery; FAINT heart never won fair lady; GIVE and take is fair play; if SAINT Paul’s day be fair and clear, it will betide a happy year; SAINT Swithun’s day if thou be fair for forty days it will remain; TURN about is fair play.
FAITH will move mountains
With allusion to MATTHEW xvii. 20 (AV) If ye have faith as a grain of mustard seed, ye shall say unto this mountain; Remove hence to yonder place; and it shall remove. Cf. I CORINTHIANS xiii. 2 (AV) though I have all faith; so that I could remove mountains; and have not charity, I am nothing.

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