The word "law" in the vocabulary of religious Jews, Christians, and Muslims means the divinely ordained law of the Ten Commandants, and the Mosaic law enunciated in the last three books of the Pentateuch.
In the first two of these three religions, the ten Commandment are laws individuals are obliged to observe and honor.
But for Christians, both Catholic, and Protestant, what Jesus Christ called the two precepts of charity replace the Mosaic law. The two precepts of charity are to love God with all thy heart and all thy soul, and thy neighbor as thyself. On these two precepts, Christ tell us, "hang the law and the prophets." For Muslims, however, the Koran is a book of laws that deal with the everyday conduct of the faithful.
The law that is taught in our law schools is the human-made or positive law of the various jurisdictions, and also the underlying law of the U.S. Constitution, which all federal officeholders swear to uphold and all citizens regard as the fundamental safeguard of their natural rights.
The thing that connects the Constitution of the United States to the human-made laws of the federal government of the fifty-state jurisdictions is the natural law. Religious persons believe that the natural law is instilled in our minds and hearts by God, but even atheists can appeal to the natural law as the law of reason concerning what ought and ought not to be sought and what ought and ought not to be done.
It is the law of reason that proclaims our natural rights. Natural rights are the same at all times and places, but in the course of history there has been a growing recognition of such rights.
Chattel slavery was always a violation of man's natural right to liberty, but this natural right was not always recognized by most countries, and it is still far from being universally observed.
In the United States today there is still dispute between those who advocate a strict interpretation of the Constitution and those who think that reason can instruct us with regard to rights not mentioned in the Constitution or its Bill of Rights.
The strict constitutionalists have difficulty in explaining our government's foreign policy -- one that condemn those nations in the world which do not respect the natural rights of human beings. Strict constitutionalists have difficulty also in recognizing that if chattel slavery is wrong now, it was wrong when it was incorporated into the Constitution originally, which was thus itself in that extent wrong, and made right only with the Thirteenth, Fourteenth, and Fifteenth Amendments.
If I am correct in thinking that every human being has a right to a decent livelihood, then it must be inferred that the United States has not yet become a nation that secures all the natural rights of its citizens. It may not succeed in doing so until late in the next century.