Which strain at a gnat ... - This is a proverb. There is, however, a mistranslation or misprint here, which makes the verse unmeaning. “To strain” at a “gnat” conveys no sense. It should have been to strain out a gnat; and so it is printed in some of the earlier versions, and so it was undoubtedly rendered by the translators. The common reading is a “misprint,” and should be corrected. The Greek means to “strain” out by a cloth or sieve.
A gnat - The gnat has its origin in the water; not in great rivers, but in pools and marshes In the stagnant waters they appear in the form of small “grubs” or “larvae.” These larvae retain their form about three weeks, after which they turn to chrysalids, and after three or four days they pass to the form of gnats. They are then distinguished by their well-known sharp sting. It is probable that the Saviour here refers to the insect as it exists in its “grub” or “larva” form, before it appears in the form of a gnat. Water is then its element, and those who were nice in their drink would take pains to strain it out. Hence, the proverb. See Calmet’s Dict., art. “Gnat.” It is used here to denote a very small matter, as a camel is to denote a large object. “You Jews take great pains to avoid offence in very small matters, superstitiously observing the smallest points of the law, like a man carefully straining out the animalculae from what he drinks, while you are at no pains to avoid great sins - hypocrisy, deceit, oppression, and lust - like a man who should swallow a camel.” The Arabians have a similar proverb: “He eats an elephant, and is suffocated with a gnat.” He is troubled with little things, but pays no attention to great matters.