The Bill of Rights was inspired by three remarkable documents: John Locke's 1689 thesis, "Two Treatises of Government," regarding the protection of "property" (in the Latin context, proprius, or one's own "life, liberty and estate"); in part from the Virginia Declaration of Rights authored by George Mason in 1776 as part of that state's Constitution; and, of course, in part from our Declaration of Independence authored by Thomas Jefferson.
Though the Bill of Rights is commonly referred to as "the first ten amendments" to our Constitution, it is important to distinguish these ten articles from amendments — the former being an integral part of our Constitution, while the latter, over the course of our nation's history, having modified it.
Because of that distinction, the addition of the Bill of Rights was hotly debated among our Founders, many of whom argued that the mere reiteration of these innate and unalienable Rights of Man within the Constitution might imply that they are somehow subject to amendment, as if granted by the state.
Alexander Hamilton argued in Federalist No. 84, "[B]ills of rights, in the sense and in the extent in which they are contended for, are not only unnecessary in the proposed constitution, but would even be dangerous. They would contain various exceptions to powers which are not granted; and on this very account, would afford a colorable pretext to claim more than were granted. For why declare that things shall not be done which there is no power to do?"
On the other hand, George Mason was among 16 of the 55 Constitutional Convention delegates who refused to sign because the document did not adequately address limitations on what the central government had "no power to do." Indeed, he worked with Patrick Henry and Samuel Adams against its ratification for that very reason.
As a result of Mason's insistence, the first session of Congress incorporated those 10 additional limitations upon the federal government for the reasons outlined by the Preamble to the Bill of Rights: "The Conventions of a number of the States having at the time of their adopting the Constitution, expressed a desire, in order to prevent misconstruction or abuse of its powers, that further declaratory and restrictive clauses should be added: And as extending the ground of public confidence in the Government, will best insure the beneficent ends of its institution."
Read in context, the Bill of Rights is both an affirmation of innate "unalienable rights" of man, and a clear proscription upon any central government infringement of those rights. As oft trampled and abused as the Bill of Rights is by those who've sworn an oath "to Support and Defend" our Constitution, most notably "judicial supremacists," or the "despotic branch" as Jefferson called the judiciary, Patriots must remain ever vigilant in order to sustain our rights.