. . . a constitution, intended to endure for ages to come, and consequently, to be adapted to the various crises of human affairs. - John Marshall

It is the peculiar province of the legislature to prescribe general rules for the government of society; the application of those rules to individuals in society would seem to be the duty of other departments.

But all legislative powers appertain to sovereignty. The original power of giving the law on any subject whatever is a sovereign power [...] All admit that the Government may legitimately punish any violation of its laws, and yet this is not among the enumerated powers of Congress. The right to enforce the observance of law by punishing its infraction might be denied with the more plausibility because it is expressly given in some cases. Congress is empowered "to provide for the punishment of counterfeiting the securities and current coin of the United States," and "to define and punish piracies and felonies committed on the high seas, and offences against the law of nations." The several powers of Congress may exist in a very imperfect State, to be sure, but they may exist and be carried into execution, although no punishment should be inflicted, in cases where the right to punish is not expressly given. Take, for example, the power "to establish post-offices and post-roads." This power is executed by the single act of making the establishment. But from this has been inferred the power and duty of carrying the mail along the post road from one post office to another. And from this implied power has again been inferred the right to punish those who steal letters from the post office, or rob the mail. It may be said with some plausibility that the right to carry the mail, and to punish those who rob it, is not indispensably necessary to the establishment of a post office and post road. This right is indeed essential to the beneficial exercise of the power, but not indispensably necessary to its existence. So, of the punishment of the crimes of stealing or falsifying a record or process of a Court of the United States, or of perjury in such Court. To punish these offences is certainly conducive to the due administration of justice. But Courts may exist, and may decide the causes brought before them, though such crimes escape punishment. The baneful influence of this narrow construction on all the operations of the Government, and the absolute impracticability of maintaining it without rendering the Government incompetent to its great objects, might be illustrated by numerous examples drawn from the Constitution and from our laws. The good sense of the public has pronounced without hesitation that the power of punishment appertains to sovereignty, and may be exercised, whenever the sovereign has a right to act, as incidental to his Constitutional powers. It is a means for carrying into execution all sovereign powers, and may be used although not indispensably necessary. It is a right incidental to the power, and conducive to its beneficial exercise.

The powers of the legislature are defined, and limited; and that those limits may not be mistaken, or forgotten, the constitution is written. To what purpose are powers limited, and to what purpose is that limitation committed to writing, if these limits may, at any time, be passed by those intended to be restrained? The distinction, between a government with limited and unlimited powers, is abolished, if those limits do not confine the persons on whom they are imposed, and if acts prohibited and acts allowed, are of equal obligation. It is a proposition too plain to be contested, that the constitution controls any legislative act repugnant to it; or, that the legislature may alter the constitution by an ordinary act.