The three golden balls. The emblem of St. Nicholas, who is said to have given three purses of gold to three virgin sisters to enable them to marry.
As the cognisance of the Medici family they probably represent three golden pills—a punning device on the name. Be this, however, as it may, it is from the Lombard family (the first great moneylenders in England) that the sign has been appropriated by pawnbrokers. (See Mugello for another account.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894