A dictionary of Proverbs (Oxford Paperback Reference)

HONEY catches more flies than vinegar
Soft or ingratiating words achieve more than sharpness. cf. St. Francis de Sales (1567­1622) in L. de la Riviere Vie de..Frangois de Sales (1624) 584: souvenez-vous que I’on prends plus de mouches avec une cuilleree de miel qu’avec cent barils de vinaigre (remember that one catches more flies with a spoonful of honey than with a hundred barrels of vinegar).

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  1666 G. TORRIANO Italian Proverbs 149 Honey gets more flyes to it, than doth viniger. 1744 B. FRANKLIN Poor Richard’s Almanack (Mar.) Tart Words make no Friends: spoonful of honey will catch more flies than Gallon of Vinegar. 1955 W. C. MACDONALD Destination Danger X. I .. know the old saying relative to honey catching more flies than vinegar. .. If this is an act, you might as well save your breath. 1996 Washington Post 25 Oct. B4 Ask his advice frequently, and thank him profusely for his wisdom and guidance. Remember that old adage ‘You can catch more flies with honey than with vinegar.’ "tact
  

honey see also where BEES are, there is honey; one DAY honey, one day onion.
There is HONOUR among thieves
The concept is found in c 1622-3 Soddered Citizen (1936) 1. 305 Theeues haue betweene themselues, a truth, And faith, which they keepe firme, by which They doe subsist; 1703 P. A. MOTTEUX Don Quixote II. lx. The old proverb still holds good, Thieves are never rogues among themselves.

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  1802 J. BENTHAM Works (1843) IV 225 A sort of honour may be found (according to a proverbial saying) even among thieves. 1823 J. BEE Dict. Turf 98 ‘There is honour among thieves, but none among gamblers,’ is very well antithetically spoken, but not true in fact. 1984 J. REEVES Murder before Matins vi. Honour among thieves was an empty phrase to all three of them: every professional criminal they’d known would sell his sidekick unhesitatingly if the price were right. 2002 R. J. BERNSTEIN Radical Evil 25 And a moral scoundrel may occasionally do what duty requires (honor among thieves). ■ honour; wrong-doers