The Eighth Commandment: Lying
By Father Kenneth Wasilewski
Since March, with the pandemic and other societal issues making headlines, it seemed appropriate to address some of the moral issues surrounding those things. However, perhaps a return to some of the more “general” moral issues would be a welcome break. To that end, it seems appropriate to pick up where I left off before the pandemic began.
Previously, I had been looking at the Eighth Commandment, “You shall not bear false witness against your neighbor.” Some of the issues covered involved the importance of truthfulness, concerns over a person’s reputation, and offenses like detraction and calumny. But one of the most obvious and common offenses against the Eighth Commandment has yet to be discussed; namely, lying. 
The Catechism of the Catholic Church, quoting St. Augustine, defines a lie as, “speaking a falsehood with the intention of deceiving” (CCC 2482). The wording of this definition is very important in the Church’s understanding of what it means to “lie.” Really there are two main parts. 
First, one must “speak a falsehood.” “Speaking” in this case can really mean communicating in any way. I need not speak verbally to lie. I can do so in any number of ways where I “communicate” that which is false. 
This definition also implies that people have the knowledge that what they are saying or communicating is not true. There can be many times when people communicate something that is not true, but sincerely believe that it is true, or understand it to be true. If I say something that I believe to be true which is later revealed not to be true, I can not be said to have lied. It simply means that I was wrong or made a mistake or misunderstood. Knowledge of what is actually true and false is a prerequisite for lying. 
There may also be times when I should know what is true and false, but if I honestly don’t, I cannot be called a liar (That’s not to say there’s no moral blame in such a case — perhaps we’re guilty of being irresponsible or negligent, if we had an obligation to know something — but these are other issues). 
A lie only occurs if I know what the truth is and choose to say something other than the truth. We can probably all think of our own examples when we said something that we believed was true, but later found out it wasn’t. Someone may call us a liar or believe that we are one, but if I truly didn’t know I was speaking a falsehood, then I am not guilty of lying. 
The second part of that definition from the catechism is also very important and supports what has already been said regarding our knowledge of what is true and false. Having the “intention of deceiving” is also essential to a lie. 
This means that I not only know what is true and false, but that I intend to convince someone that what I know to be false is actually true. I’m speaking or communicating in the manner that I am so that someone believes that what I know to be false is true or that what I know to be true is taken to be false. I intend to deceive someone about what is true and false. 
It is only when both of these parts are present (speaking a falsehood and intending to deceive) that a lie has actually taken place. 
With all of that said, there can still be other issues about truth telling and deception that need to be looked at, because for most of us there may be times when we feel justified in saying something that we know is not true or when we say something that is true, but in a way that is deceptive.
 Can there be times when doing so is acceptable, morally speaking? We’ll look at some of these questions in a future column.