Natural Law: The natural law is a law of morality written upon the conscience of every person.  It’s a law of morality that we simply know by nature.  This law, acting in accord with human reason, calls us to do good and forbids us to sin. There are two key aspects of the natural law we see in this definition.  First, the natural law is “engraved in the soul of each and every man,” and, second, this law calls man “to do good and forbidding him to sin” (CCC #1954).

Think about your knowledge of right and wrong.  Where did it come from?  Is it purely the result of what you’ve been taught by parents and others throughout your life?  Or is there a source that goes beyond that which you were taught?  The truth is that there are many things we simply know to be good and other things we know to be wrong.  This is because God has written His law upon our human reason.  

For example, why do you know it’s wrong to kill someone?  Or why do you know it’s wrong to steal a large sum of money from a neighbor?  Is it only because you were taught this way?  No, there is more to it.  It’s true that being taught right from wrong helps us, but deep down we do know certain basic moral principles.  We know them because we have to know them.  And we have to know them because God has made His law part of our very nature.

The problem is that our human nature is “messed up,” so to speak.  We have been greatly affected by Original Sin and what we call “concupiscence.”  This means that our very nature is distorted and disordered.  As a result, that law of God written upon our conscience is blurred and confused.  If we had a perfect human nature, all would be clear, but we don’t.  Therefore, the natural law is confused at times.  But with that said, if we try to seek the truth within our human reason, we will at very least arrive at the most basic of moral principles and will be able to be guided by them.  And, as explained above, ignoring the natural moral law does not make it go away.

To be continued