Look up Charles de Secondat, Baron de Montesquieu, and you will find plenty of scholars who have written quite knowledgeably about the man and what he wrote. What you will not find are many American citizens who have studied what the man wrote, and that’s shameful. Montesquieu’s The Spirit of laws, published in 1748, had an enormous influence on our nation’s Founding Fathers and The United States Constitution. For example, to strengthen their arguments, both James Madison and Alexander Hamilton repeatedly cited Montesquieu in The Federalist Papers. Madison also noted in The Journal of the Debates in the Convention that the delegates referenced Montesquieu several times.
What would we learn by reading The Spirit of laws today? We would learn how much we have be misled. Consider, for example, how the Montesquieu’s great book begins.
Laws, in their most general signification, are the necessary relations arising from the nature of things. In this sense all beings have their laws: the Deity His laws, the material world its laws, the intelligences superior to man their laws, the beasts their laws, man his laws.
They who assert that a blind fatality produced the various effects we behold in this world talk very absurdly; for can anything be more unreasonable than to pretend that a blind fatality could be productive of intelligent beings?
There is, then, a prime reason; and laws are the relations subsisting between it and different beings, and the relations of these to one another.
God is related to the universe, as Creator and Preserver; the laws by which He created all things are those by which He preserves them. He acts according to these rules, because He knows them; He knows them, because He made them; and He made them, because they are in relation to His wisdom and power.
Since we observe that the world, though formed by the motion of matter, and void of understanding, subsists through so long a succession of ages, its motions must certainly be directed by invariable laws; and could we imagine another world, it must also have constant rules, or it would inevitably perish.
Thus the creation, which seems an arbitrary act, supposes laws as invariable as those of the fatality of the Atheists. It would be absurd to say that the Creator might govern the world without those rules, since without them it could not subsist.
These rules are a fixed and invariable relation. In bodies moved, the motion is received, increased, diminished, or lost, according to the relations of the quantity of matter and velocity; each diversity is uniformity, each change is constancy. (continued here)
To determine the proper spirit of laws, Montesquieu started with the Creator and his Laws. To write our Constitution, our nation’s founders consulted the writings of the most thoughtful and respected men of their age. Consider this excerpt from Wikipedia.
Delegates used two streams of intellectual tradition, and any one delegate could be found using both or a mixture depending on the subject under discussion: foreign affairs, the economy, national government, or federal relationships among the states. The Virginia Plan recommended a consolidated national government, generally favoring the most populated states. It used the philosophy of John Locke to rely on consent of the governed, Montesquieu for divided government, and Edward Coke to emphasize civil liberties. The New Jersey Plan generally favored the less populated states, using the philosophy of English Whigs such as Edmund Burke to rely on received procedure, and William Blackstone to emphasize sovereignty of the legislature. (from here)
When they spoke of their beliefs about how a society should govern itself, Locke, Coke, Burke, and Blackstone also had no trouble deferring to the will of our Creator. Check for yourself.
- Two Treatises of Government Book by John Locke
- Institutes of the Lawes of England by Edward Coke: All four institutes are available from Google Books: First Part  (Volume 1 of 1832 ed.)   (1853 American ed. in 2 vols) Second Part  (1797 ed.) Third Part  (1669 ed.)  (1797 ed.) Fourth Part  (1671 ed.) (1797 ed.)
- BURKE’S WRITINGS AND SPEECHES by Edmund Burke
- Commentaries on the Laws of England by William Blackstone
Although our Constitution — because it respects each citizen’s God-given rights — may be secular work, creating it was not a godless work. Instead, we have a thoughtful document written by Godly men trying to protect the God-given rights of their families, friends and neighbors.