A dictionary of Proverbs (Oxford Paperback Reference)

If every man would SWEEP his own doorstep the city would soon be clean

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  1624 T. ADAMS Temple 65 When we would haue the street cleansed, let euery man sweep his owne doore, and it is quickly done. 1666 G. TORRIANO Italian Proverbs 41 If every one will sweep his own house, the City will be clean. 1930 Times 25 Mar. 10 It appears to be hard to draw a clear distinction between deciding a question of right and wrong for one’s self and deciding it for others. .. ‘If every man would sweep his own doorstep the city would soon be clean.’ 2002 Washington Times 14 Aug. B5 You’re right —and if everyone swept his own doorstep, this world would be a cleaner place. ■ cleanliness; society
  

SWEEP the house with broom in May, you sweep the head of the house away
There was a widespread folk belief associating broom with witches and magic; hence, flowering broom was considered unlucky and a harbinger of death in any house into which it was brought.

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  1873 Folk-Lore Record I. 52 The old gentleman.. strictly forbade green brooms being used in his house during the month of May, and, as a reason for the prohibition, used to quote the adage—’If you sweep the house with broom in May, You’ll sweep the head of that house away’. 1943 H. C. BAILEY Mr. Fortune Finds Pig (1948) xvi. 64 ‘What hadn’t you thought of?’ Rosen demanded sharply.’ “Sweep the house with broom in May”, Reggie murmured, ‘“You sweep the head of the house away. ■ calendar lore; superstition
  

sweep see also NEW brooms sweep clean.
With a SWEET tongue and kindness, you can drag an elephant by a hair
Of Iranian origin; a variant is ‘. . drag a snake..’.

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  2001 Seattle Times 31 Mar. All With a sweet tongue and kindness you can drag an elephant by a hair.—Persian proverb. 2006 Times 4 Sept. 20 Another local maxim appears to capture the outside world’s response to Iran’s nuclear ambitions. It is akin to an ancient remark: ‘A gentle hand may lead an elephant by a hair.’ For that is clearly the approach that Kofi Annan, on behalf of the United Nations, and Javier Solana, for the European Union, are adopting. "gentleness; tact