A dictionary of Proverbs (Oxford Paperback Reference)

coward see a BULLY is always a coward; CONSCIENCE makes cowards of us all.
COWARDS die many times before their death
The popular form is a misquotation of Shakespeare (see quot. 1599) Cf. 1596 DRAYTON Mortimeriados S1 Every houre he dyes, which ever feares.

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  1599 SHAKESPEARE Julius Caesar II. ii. 32 Cowards die many times before their deaths: The valiant never taste of death but once. 1800 M. EDGEWORTH Castle Rackrent p. xliv. In Ireland, not only cowards, but the brave ‘die many times before their death.’ 1927 Sphere 3 Dec. 414 It is true that cowards die many times before their death, and Noel Coward will come back again and again, and.. win his niche among the great dramatists. ■ cowardice
  

The COWL does not make the monk
Appearance is no reliable guide to a person’s true character. Cf. medieval L. cucullus non facit monachum, the cowl does not make the monk; a 1250 Ancrene Wisse (1962) 10 Her in is religiun, nawt i the wide hod ne i the blake cape.

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  1387 T. USK Testament of Love in Chaucer Complete Works (1897) II. xi. For habit maketh no monk; ne weringe of gilte spurres maketh no knight. 1588 R. GREENE Pandosto IV. 289 Trueth quoth Fawnia, but all that weare Cooles [cowls] are not Monkes. 1613 SHAKESPEARE Henry VIII III. i. 23 They should be good men, their affairs as righteous; But all hoods make not monks. 1820 SCOTT Abbot II. xi. ‘Call me not doctor.. since I have laid aside my furred gown and bonnet.’.. ‘O, sir.. the cowl makes not the monk.’ 1891 G. B. SHAW Music in London (1932) I. 217 Such impostures are sure of support from the sort of people.. who think that it is the cowl that makes the monk. 1940 ‘S. ASHE’ I Am Saxon Ashe 58 ‘Darling—there is a Latin tag that runs: A cowl does not necessarily hide a monk. Let me vary it for you: the clown is not necessarily a fool.’ ■ appearance, deceptive