American Tract Society Bible Dictionary
A small winged stinging insect, a mosquito, spoken of in the proverbial expression, Matthew 23:24 , "Ye strain at a gnat, and swallow in a camel," which should read, as it did in the first English translations, "Ye strain out a gnat," etc. The expression alludes to the Jewish custom of filtering wine, for fear of swallowing any insect forbidden by the law as unclean, Leviticus 11:23; and is applied to those who are superstitiously anxious in avoiding small faults, yet do not scruple to commit great sins.
These files are public domain and are a derivative of the topics are from American Tract Society Bible Dictionary published in 1859.
Rand, W. W. Entry for 'Gnat'. American Tract Society Bible Dictionary. https://www.studylight.org/dictionaries/eng/ats/g/gnat.html. 1859.