"The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
What this means is that unless it is specifically stated in the United States Constitution, the federal government can not do it. The first amendment states, in part, that Congress shall make no law regarding the establishment of a religion. This means that Congress can not tell everyone that they have to belong to the Church of America in order to be a citizen. This was written by people who were forced, by virtue of being British citizens, to belong to the Church of England. However, this amendment was not binding on the states. Massachusetts, for example, has in their constitution (written after the ratification of the United States Constitution and Bill of Rights) an official state religion. Other states had official state religions as well, but that is ok, because the Bill of Rights was written to limit the powers of the federal government, not state governments.
Powers that are not delegated to the federal government are reserved to the states. Powers such as education, health care, gun control. None of these are mentioned in the constitution, except for gun control, which is not allowed. Gun control is mentioned in the negative by the second amendment which says "...the right of the people to keep and bear Arms, shall not be infringed." But again, this is meant for the federal government, not the states.
The government of the United States is supposed to do the will of the people, not force the people to do their will. For too long, the federal government has been assuming more power than delegated to them. For too long, they have been taking the rights of the people away. WE THE PEOPLE need to remind them that they are to serve us, not the other way around. WE THE PEOPLE need to pay attention to who we send to Washington DC. WE THE PEOPLE need to vote out our representatives if they don't represent us. WE THE PEOPLE need to take back our rights that have been slowly stripped from us by representatives who do not represent.