God-given ????
What if you don’t Believe in a God ????
Natural law is a theory in ethics and philosophy that says that human beings possess intrinsic values that govern their reasoning and behavior. Natural law maintains that these rules of right and wrong are inherent in people and are not created by society or court judges.
In law, common law, also known as judicial precedent, judge-made law, or case law, is the body of law created by judges and similar quasi-judicial tribunals by virtue of being stated in written opinions.
The defining characteristic of “common law” is that it arises as precedent. In cases where the parties disagree on what the law is, a common law court looks to past precedential decisions of relevant courts, and synthesizes the principles of those past cases as applicable to the current facts.
If a similar dispute has been resolved in the past, the court is usually bound to follow the reasoning used in the prior decision (a principle known as stare decisis). If, however, the court finds that the current dispute is fundamentally distinct from all previous cases (called a "matter of first impression"), and legislative statutes are either silent or ambiguous on the question, judges have the authority and duty to resolve the issue (one party or the other has to win, and on disagreements of law, judges make that decision).
The court states an opinion that gives reasons for the decision, and those reasons agglomerate with past decisions as precedent to bind future judges and litigants.
Common law, as the body of law made by judges, stands in contrast to and on equal footing with statutes which are adopted through the legislative process, and regulations which are promulgated by the executive branch (the interactions among these different sources of law are explained later in this article). Stare decisis, the principle that cases should be decided according to consistent principled rules so that similar facts will yield similar results, lies at the heart of all common law systems.
Source: https://en.wikipedia.org/wiki/Common_law#Basic_principles_of_common_law
Whether you believe in a God or not natural law is basic common sense but not written down (unless you count the 10 commandments) whereas common law is written down. Judges have nothing to do with common law, a jury does tho. Judges just oversee the process.