Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.
Constitution
Source: Constitution of the United States of America
The Constitution, in addition to delegating certain enumerated powers to Congress, places whole areas outside the reach of Congress' regulatory authority. The First Amendment, for example, is fittingly celebrated for preventing Congress from "prohibiting the free exercise" of religion or "abridging the freedom of speech." The Second Amendment similarly appears to contain an express limitation on the government's authority....This Court has not had recent occasion to consider the nature of the substantive right safeguarded by the Second Amendment. If, however, the Second Amendment is read to confer a personal right to "keep and bear arms," a colorable argument exists that the Federal Government's regulatory scheme, at least as it pertains to the purely intrastate sale or possession of firearms, runs afoul of that Amendment's protections.
Clarence Thomas
Source: 1997, Concurrence, Printz v. United States