Recorded in Guan Hanqing's Yuan drama 《救风尘》: 三言两句，肯写休书 ('in a few words he agreed to write the divorce letter'). The early form used 两句 (two sentences); the 两语 variant became standard later.
usage
Often in two classic frames: 三言两语说不清 ('can't be said in a few words', i.e. it's complicated) and 三言两语就… ('in just a few words, someone did…', praising concision). The number pattern 三…两… is idiomatic and not literal.
