Hunting two Hares
He who hunts two hares leaves one and loses the other. No one can do well or properly two things at once. “No man can serve two masters.”
“Poursuis deux lièvres, et les manques” (La Fontaine). “On ne peut tirer à deux cibles.”
“Duos qui sequitur leporcs, neutrum capit.” “Simul sorbere ac flare non poseum.”
Like a man to double business bound I stand in pause where I shall first begin, And both neglect.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894