A dictionary of Proverbs (Oxford Paperback Reference)

A YOUNG man married is a young man marred

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  1589 G. PUTTENHAM Art of English Poesy III. xix. 173 The maide that soone married is, soone marred is. 1602 SHAKESPEARE All’s Well that ends Well II. iii. 291 A young man married is a man that’s marr’d. 1961 R. KIRK Old House of Fear i. Don’t forget this, though, Duncan—’You can grave it on his tombstone, you can cut it on his card: A young man married is a young man marred.’ ■ marriage; youth
  

YOUNG men may die, but old men must die
Cf. the words of a Roman noblewoman rejecting an elderly suitor after the death of her young husband: juvenis quidem potest cito mori; sed senex diu vivere non potest, a young man may indeed die early, but an old man cannot live long (quoted by ST. JEROME, Letter cxxvii. 2).

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  1534 MORE Dialogue of Comfort (1553) II. ii. As the younge man maye happe some time to die soone, so the olde man can never liue long. 1623 W. CAMDEN Remains concerning Britain (ed. 3) 276 Young men may die, but old men must die. 1758 LADY M. W. MONTAGU Letter 5 Sept. (1967) III. 174 According to the good English Proverb, young people may die, but old must. 1863 B. I. WILEY Life of Billy Yank (1952) xii. That is the Way of the World. The old must die and the young may die. 1970 ‘D. CRAIG’ (title) Young men may die. 1993 ‘C. AIRD’ Going Concern (1994) i. 9 Mary-Louise was the holiday party’s language specialist and immediately said: ‘“The young die sometimes, but the old always die.” That’s an old Breton proverb.’ ■death; necessity; old age
  

YOUNG saint, old devil

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  c 1400 Middle English Sermons from MS Royal 18 B xxiii (EETS) 159 Itt is a comond prouerbe bothe of clerkes and of laye men, ‘younge seynt, old dewell’. 1552 H. LATIMER Seventh Sermon, Lord’s Prayer in Sermons (1844-5) 431 The old proverb, ‘Young saints, old devils’.. is.. the devil’s own invention; which would have parents negligent in bringing up their children in goodness. 1636 S. WARD Collection of Sermons & Treatises 269 Young Saints, will prove but old Devils.. But.. such as proove falling starres, never were ought but meteors. 1936 V. MCHUGH Caleb Catlum’s America xxvii. Young saint, old devil.. looks to me like you been leadin’ too virtyus a life. "good and evil; human nature; youth
  

young see also BETTER be an old man’s darling than a young man’s slave; whom the GODS love die young; the GOOD die young; HANG a thief when he’s young, and he’ll no’ steal when he’s old; you cannot put an OLD head on young shoulders.