"The sword and the purse, all the external relations, and no inconsiderable portion of the industry of the nation, are entrusted to its government. It can never be pretended that these vast powers draw after them others of inferior importance, merely because they are inferior. Such an idea can never be advanced. But it may with great reason be contended, that a government, entrusted with such ample powers, on the due execution of which the happiness and prosperity of the nation so vitally depends, must also be entrusted with ample means for their execution. The power being given, it is the interest of the nation to facilitate its execution. It can never be their interest, and cannot be presumed to have been their intention, to clog and embarrass its execution by withholding the most appropriate means."

“Should Congress, in the execution of its powers, adopt measures which are prohibited by the constitution; or should Congress, under the pretext of executing its powers, pass laws for the accomplishment of objects not entrusted to the government; it would become the painful duty of this tribunal, should a case requiring such a decision come before it, to say that such an act was not the law of the land. But where the law is not prohibited, and is really calculated to effect any of the objects entrusted to the government, to undertake here to inquire into the degree of its necessity, would be to pass the line which circumscribes the judicial department, and to tread on legislative ground. This court disclaims all pretensions to such a power.”

“The subject is the execution of those great powers on which the welfare of a Nation essentially depends. It must have been the intention of those who gave these powers, to insure, as far as human prudence could insure, their beneficial execution. This could not be done by confiding the choice of means to such narrow limits as not to leave it in the power of Congress to adopt any which might be appropriate, and which were conducive to the end. This provision is made in a constitution intended to endure for ages to come, and, consequently, to be adapted to the various crises of human affairs.”

“Supreme Court Historical Society: John Marshall”

“It has been said, that the people had already surrendered all their powers to the State sovereignties, and had nothing more to give. But, surely, the question whether they may resume and modify the powers granted to government does not remain to be settled in this country. Much more might the legitimacy of the general government be doubted, had it been created by the States. The powers delegated to the State sovereignties were to be exercised by themselves, not by a distinct and independent sovereignty, created by themselves. To the formation of a league, such as was the confederation, the State sovereignties were certainly competent. But when, "in order to form a more perfect union," it was deemed necessary to change this alliance into an effective government, possessing great and sovereign powers, and acting directly on the people, the necessity of 'referring it to the people, and of deriving its powers directly from them, was felt and acknowledged by all.”

“We admit, as all must admit, that the powers of the Government are limited, and that its limits are not to be transcended. But we think the sound construction of the Constitution must allow to the national legislature that discretion with respect to the means by which the powers it confers are to be carried into execution which will enable that body to perform the high duties assigned to it in the manner most beneficial to the people. Let the end be legitimate, let it be within the scope of the constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the constitution, are constitutional.”

“We have no more right to decline the exercise of jurisdiction which is given, than to usurp that which is not given. The one or the other would be treason to the constitution.”