What are the…
naughty figs

See: Jeremiah 24:2

“The bad figs may have been such either from having decayed, and thus been reduced to a rotten condition, or as being the fruit of the sycamore, which contains a bitter juice” (Henry Baker Tristram, The Natural History of the Bible).

The inferiority of the fruit is here referred to as an emblem of the rejected Zedekiah and his people.