A few observations:
Common conceptions to the contrary, the first ten amendments to the Constitution do not grant people their rights.
The First Amendment does not say that, henceforth, people shall have a right to establish a religion or to speak freely. Instead, it says that “Congress shall make no law respecting an establishment of religion…or abridging the freedom of speech.” The second Amendment does not say that the people now have a right to bear arms. It says that “the right of the people to keep and bear Arms, shall not be infringed.”
This is not a matter of semantics. The framers knew that they could not possibly name all of the legitimate rights of the people. Indeed, as Hamilton expressed in Federalist 84, there was a danger in trying to do so, for if the list left anything out (as it surely would), then there would be a presumption that people lacked the omitted rights and this might be used as a “pretext to claim” that the federal government possessed more than the strictly enumerated powers laid out in Constitution.
So instead of enumerating the rights of the people, the Bill of Rights talks about the things that the Federal government may not do: “Congress shall make no law…”, “the right…shall not be infringed”, “the right of the people to be secure in their persons…shall not be violated”, “In Suits at common law…the right of trial by jury shall be preserved”, “excessive bail shall not be required.”
Each of these is a limitation on the powers of the government, not a positive grant of a right to the people (I’ll concede that the Sixth Amendment, which says that in criminal prosecutions the accused “shall enjoy the right to a speedy trial…” comes close to a positive grant; but even there, the idea is that the government cannot lock you up without a trial).
The handy thing about this wording is that it sets up the presumption that we don’t have to go to the government to ask for our rights. Our rights existed before government was established. And if the federal government were to one day fall, then our rights would still exist. This was a central tenet of the Enlightenment philosophy and it can be found in the writings of Locke, Mason, and Jefferson, among many others.
The framers thought of these rights as God-given. But if you prefer a secular spin on it, you can imagine that they are reason-given. The point is that they are not government-given.