The "state" differs from other forms of political organization in very profound ways. Whereas "other forms of political organization" can refer to political parties, ideologically-oriented public policy or public advocacy organizations, political fund-raising organizations, and so on, "state" has a more substantive meaning.
Political scientists and international affairs scholars routinely think in terms of "state" and "nonstate" actors when discussing the role of government and nongovernmental organizations in the making of public policy. The term "state" has certain connotations directly associated with governing institutions that, at least in a democracy, enjoy the consent of the governed. "States" are generally sovereign entities the existence of which are a result of political processes, including elections and parliamentary systems. They are vested with the authority to collect taxes, and to use that revenue for the common good -- all of which is very different from the function of other political organizations.
Within the context of religion, the role of the state varies from country to country. In the United States, nongovernmental political organizations are free to advocate on behalf of religious beliefs, and to use their money in support of those beliefs. The government, or state, on the other hand, is strictly proscribed from practicing any such role. Article VI of the United States Constitution states:
"This Constitution, and the laws of the United States which shall be made in pursuance thereof...shall be the supreme law of the land; and the judges in every state shall be bound thereby, anything in the Constitution or laws of any State to the contrary notwithstanding...The Senators and Representatives before mentioned, and the members of the several state legislatures, and all executive and judicial officers...shall be bound by oath or affirmation to support this Constitution; but no religious test shall ever be required as a qualification to any office or public trust under the United States." [Emphasis added]
In addition, in a significant reaffirmation of the separation of Church and State envisioned in the Constitution, the First Amendment, adopted in 1791, adds:
"Congress shall make no law respecting an establishmen of religion, or prohibiting the free exercise thereof..."
Again, the state is a political entity, but one that exercises sovereign powers that place it in a very different category than other forms of political organization. Political parties can be closely tied to religious denominations but, once in power, the responsibilities of governing impose a burden that is both greater and, in the case of religion, more limited.