A dictionary of Proverbs (Oxford Paperback Reference)

A GOLDEN key can open any door

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  1580 LYLY Euphues & his England II. 71 Who is so ignorant that knoweth not, gold be a key for euery locke, chieflye with his Ladye. 1660 W. SECKER Nonsuch Professor II. ix. The gates of the new Jerusalem.. are not got open by golden keys. 1842 TENNYSON Poems (1969) 694 Every door is barr’d with gold, and opens but to golden keys. 1945 F. THOMPSON Lark Rise xix. Their better-educated neighbours.. did not call on the newly rich family. That was before the days when a golden key could open any door. "bribery and corruption; money
  

golden see also SILENCE is golden; SPEECH is silver, but silence is golden.
If you can’t be GOOD, be careful
Cf. mid 11th-cent. L. si non caste tamen caute; 1303 R. BRUNNE Handlyng Synne (EETS) 1. 8316 The apostle seyth thys autoryte [dictum], ‘Gyf thou be nat chaste, be thou pryue [secret].’ 1528 W. TYNDALE Obedience of Christian Man 73 As oure lawears saye, si non caste tamen caute, this is, if ye live not chaste, se ye cary clene [act properly], and playe the knave secretly.

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  1903 A. M. BINSTEAD Pitcher in Paradise viii. Always bear in mind what the country mother said to her daughter who was coming up to town to be apprenticed to the Bond Street millinery, ‘For heaven’s sake be good; but if you can’t be good, be careful.’ 1907 B. SCOTT (song-title) If you can’t be good—be careful. 1982 S. GRANT DUFF Parting of Ways xvii. Tommy.. gave me a stern warning. .. ‘Never meet a German in Prague.. Be good, and if you can’t, be very careful.’ "caution
  

A GOOD beginning makes a good ending

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  c 1300 South-English Legendary (EETS) I. 216 This was atte uerste me thingth [it seems to me] a god bygynnynge. Ther after was the betere hope to come to god endynge. c 1350 Douce MS 52 no. 122 Of a gode begynnyng comyth a gode endyng. 1710 S. PALMER Proverbs 1 A good Beginning makes a good End. .. ‘Tis a great point of Wisdom . . to begin at the right end. 1850 ‘M. TENSAS’ Odd Leaves from Life of Louisiana ‘Swamp Doctor’ 109 I hope my future lot will be verification of the old adage, that a ‘bad beginning makes a good ending’, for mine is bad enough. 1934 G. WESTON His First Million Women xvi. I was brought up to believe that ‘Of a good beginning cometh a good ending.’.. ‘You can’t do a good plastering job if your laths aren’t right to begin with.’ "beginnings and endings