Matthew 23 is one of the most sustained polemical discourses in the New Testament. Jesus delivers a series of seven "woes" against the scribes and Pharisees, condemning them as hypocrites who attend to external religious observance while ignoring the internal realities it is meant to express. The sixth woe contains the phrase that gave English one of its most pungent idioms: "Woe unto you, scribes and Pharisees, hypocrites! for ye pay tithe of mint and anise and cummin, and have omitted the weightier matters of the law, judgment, mercy, and faith: these ought ye to have done, and not to leave the other undone. Ye blind guides, which strain at a gnat, and swallow a camel."
The image is comic but with a very sharp edge. In Jewish law, gnats were among the smallest creatures that could render food ritually unclean; a scrupulous observer would strain their wine or water through cloth to ensure no gnat had fallen in. Camels were among the largest unclean animals. Jesus describes a person who exercises extreme care to exclude the tiniest possible ritual impurity while swallowing, apparently without difficulty or notice, an animal enormously larger than anything they are trying to exclude. The disproportion is grotesque, designed to make the audience laugh and then realize what exactly is being laughed at.
The specific targets of the woe are people who tithe their herb gardens, a genuine expression of Pharisaic scrupulosity, the extension of tithing requirements beyond what the Torah explicitly required to cover even the smallest garden herbs, while neglecting "judgment, mercy, and faith," the central moral and relational requirements of the prophetic tradition. The tithe of mint and cummin is not wrong; Jesus says "these ought ye to have done." The problem is the hierarchy: scrupulous attention to the small while neglecting the great.
The phrase "strain at a gnat" entered English as a description of excessive attention to trivial matters, particularly in contexts where larger matters are being neglected or ignored. The full expression "strain at a gnat and swallow a camel" describes a particularly pointed form of the problem: the extreme care about small things in combination with indifference to large ones. The contrast is essential; without it, "strain at a gnat" alone might describe mere fastidiousness. With the camel, it describes disproportionate attention combined with disproportionate neglect.
In contemporary use, the phrase appears frequently in political commentary, organizational criticism, and moral discourse as a description of misplaced priorities. A regulatory agency that enforces trivial rules with great energy while ignoring major violations strains at gnats and swallows camels. A religious community that polices minor behavioral codes while tolerating injustice or abuse in its midst is subject to exactly the woe that Jesus pronounced. The phrase provides a biblical sanction for criticizing precisely this failure mode.
The rhetorical force of the phrase comes from its combination of visual vividness and proportional absurdity. Straining at a gnat is a real practice (filtering liquid); swallowing a camel is visually impossible. The image produces an effect of cognitive dissonance: the first action is careful and precise; the second is enormous and impossible. The transition between them describes something recognizable from everyday life: the displacement of careful attention onto minor concerns as a way of avoiding the major ones that are genuinely demanding.
The camel in the Matthew 23:24 image deserves specific attention. The camel was the largest domestically familiar animal in the Palestinian context and was also unclean under Levitical law. It was thus simultaneously the largest possible animal and the most obvious possible source of ritual impurity. The scrupulous Pharisee who filtered gnats from their wine to avoid the smallest possible contamination would, in Jesus's telling, happily swallow a camel whole, the very definition of major uncleanness. The absurdity is total: the person most obsessed with avoiding the smallest ritual contamination is presented as gulping down the most dramatically impure thing imaginable without noticing.
The moral insight embedded in the comic image is that scrupulosity about minor matters often functions as a defense against engagement with major ones. The person who is genuinely obsessed with the gnat-filtering may genuinely not see the camel, not because they are dishonest but because their attention has been so thoroughly captured by the small that they have lost the capacity to see the large. This is not merely a description of first-century Pharisaism but a permanent feature of moral psychology that requires active counteraction.
The image also has a self-referential dimension that increases its usefulness as a rhetorical tool. The accusation "you are straining at a gnat and swallowing a camel" is itself the kind of sharp, disproportionate response to disproportionate behavior that the metaphor describes. It calls attention to the ridiculous scale mismatch between what is being attended to and what is being ignored, and it does so in a way that makes the mismatch immediately visible. This is why the phrase functions so effectively as a critique: it makes the disproportion self-evident rather than merely arguable.