A dictionary of Proverbs (Oxford Paperback Reference)

1573 J. SANFORDE Garden of Pleasure 110V One hand washeth an other, and both wash the face. 1611 R. COTGRAVE Dict. French & English s.v. Main, One hand washes the other; applyable to such as giue vpon assurance, or hope, to be giuen vnto; or vnto such as anyway serue one anothers turne. 1836 P. HONE Diary 12 Mar. (1927) I. 203 Persons in business . . make, as the saying is, ‘one hand wash the other’. 1983 H. RESNICOW Gold Solution ix. And three years ago, Erik was on a design jury that picked the dean’s firm’s entry as a winner. One hand washes the other. 2001 P. J. O’ROURKE CEO of Sofa xii. 250 One hand washes the other: for I the Lord thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me—unless they seek counseling, of course. "reciprocity

hand see also a BIRD in the hand is worth two in the bush; COLD hands, warm heart; the DEVIL finds work for idle hands to do; the EYE of a master does more work than both his hands; FULL cup, steady hand; if IFS and ands were pots and pans, there’d be no work for tinkers’ hands; MANY hands make light work.
HANDSOME is as handsome does
Handsome denotes chivalrous or genteel behaviour, though it is often popularly taken to refer to good looks. At its second occurrence in the proverb the word is properly an adverb. For the common US equivalent, see PRETTY is as pretty does.

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  c 1580 A. MUNDAY View of Sundry Examples in J. P. Collier John A Kent (1851) 78 As the ancient adage is, goodly is he that goodly dooth. 1659 N. R. Proverbs 49 He is handsome that handsome doth. 1766 GOLDSMITH Vicar of Wakefield i. They are as heaven made them, handsome enough if they be good enough; for handsome is that handsome does. 1845 Spirit of Times 23 Aug. 297 Handsome is as handsome does. 1873 C. M. YONGE Pillars of House II. xvii. ‘Don’t you think her much better looking than Alda?’ ‘If handsome is that handsome does.’ 1979 A. WILLIAMSON Funeral March for Siegfried xxiv. ‘But he’s such a handsome, chivalrous, man.’ Handsome is as handsome does, thought York grimly. "appearance; conduct