Only in Matt. 23:24, a small two-winged stinging fly of the genus Culex, which includes mosquitoes. Our Lord alludes here to the gnat in a proverbial expression probably in common use, "who strain out the gnat;" the words in the Authorized Version, "strain at a gnat," being a mere typographical error, which has been corrected in the Revised Version. The custom of filtering wine for this purpose was common among the Jews. It was founded on Lev. 11:23. It is supposed that the "lice," Ex. 8:16 (marg. R.V., "sand-flies"), were a species of gnat.