19 Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God. (Romans 3:19 KJV)
William Burkitt’s Commentary
Observe here, Lest the Jews should think to elude or evade the force of the foregoing testimonies concerning man’s corruption and depravation, as not belonging to them, but to the Gentiles only; he tells them that what the law, that is, the books of the Old Testament, do thus say, it says to those that are under the law; that is, to those that are subjects of it, and obliged by it; to such as are under the instruction and direction of it, as the Jews are known to be; and if so, then every mouth must be stopped; Jew and Gentile both must own themselves before God, obnoxious to his wrath without being able to say anything for themselves.
Learn hence, that the holy law of God brings such plain evidence and conviction with it, that no man can have a word to speak against it: When God spreads before men the purity of his laws, and the impiety of their own lives, every man must sit down silent, and lay his hand upon his mouth, not having one word to object why sentence should not be executed, because they have all transgressed.