The Roman Catholic Magisterium infallibly teaches that some knowingly chosen acts are inherently immoral; such acts are wrong by their very nature, independent of intention and circumstances. Lying is intrinsically evil, it is wrong by its very nature (CCC 2485), and therefore it is always wrong to lie.
But this post is about the impracticality of lying. Not only is lying always immoral, it is also impractical. In my opinion, every intrinsically evil act is also impractical — it is disruptive (and sometimes even destructive) to the love of God above all else and the love of neighbor as self. Every intrinsically evil act is harmful to human relationships, to the Church, the family, and society.
Consider contraception. The Magisterium infallibly teaches that the use of contraception — the deliberate choice of any act that is inherently ordered toward depriving sexual acts of their procreative meaning — is always gravely immoral. But I notice that in Humanae Vitae, after teaching that contraception is intrinsically evil, the holy Pontiff then points out all the harm that he expects contraception to cause in the family and society if contraception were to become widespread. And it did become widespread, and the negative consequences that he anticipated did happen.
Of course, an intrinsically evil act remains immoral, even if none of the reasonably anticipated bad consequences occur. But it is worth pointing out that such bad consequences frequently do occur. It is unreasonable to expect that, if you knowingly choose an intrinsically evil act, no bad consequences will result.
Now consider lying.
1. Suppose, as an absurd hypothetical, that Jesus were to teach, in the Gospels, that lying is sometimes moral. What would the practical result be? Every commentator on the Gospels would cast doubt on any assertion or teaching, because Jesus might be lying in that verse. The veracity of every assertion by Jesus in the Gospels would be in doubt. And so how can anyone trust their eternal salvation to a Savior who says that lying is sometimes moral. He might be lying in any particular assertion. If he says, on occasion that he is not lying, that could be a lie. The surety of salvation would be lost. But all this is predicated on the absurd hypothetical, what if Jesus taught that lying is sometimes moral.
Jesus is God, and God is Truth by His very Nature. Therefore, God cannot lie and Jesus cannot lie. And since Sacred Scripture is entirely inspired by God, neither can Sacred Scripture lie, or assert a falsehood, or deny a truth.
But someone might say that Jesus cannot lie because he is God, but perhaps He could still teach that lying is sometimes moral for us.
2. So now we have a second version of this hypothetical, that Jesus teaches that He cannot lie, but that lying is sometimes moral for human persons in this life. What is the practical result? The teachings of Peter and all the Apostles and disciples would be cast into doubt. Perhaps they told some lies, in dire circumstances (such as that the Faith was severely persecuted and difficult to spread) and with only good intention (to further the spread of the Gospel). And the same doubt would then fall on all subsequent persons who taught the Gospel, including all Popes, Bishops, priests, deacons, religious, and other teachers and leaders in the Church. No one would be able to trust the teaching or word of any Church leader, and salvation through the Church would lose its surety.
So we end up with the conclusion that Jesus cannot lie, and he cannot teach that lying is sometimes moral. Which brings us to the third absurd hypothetical:
3. Suppose (a) Jesus did not teach that lying was sometimes moral, and (b) it is nevertheless true that lying is sometimes moral, and (c) Jesus simply could not tell anyone this particular teaching, because of the above-described harm that it would do.
What is the practical result of this scenario? It would imply that Christianity has two sets of teachings, public and secret. It would imply that the publically taught Gospel is not the whole truth, and is qualified and altered by a secret set of teachings. “Shhhh. Don’t tell anyone, but lying is sometimes moral. We have to make people think that lying is always wrong, so their salvation is not lost. But really it is sometimes moral. Jesus knew this truth, but He couldn’t say it.” That is the absurd result of this hypothetical.
The true Catholic Faith cannot stand if truth is subjugated to lying, for any reason, in any circumstance. If we say that lying is sometimes moral, we are in effect saying that Jesus Himself knew that lying is sometimes moral, and yet He called Satan the father of lies (Jn 8:44). We are in effect asserting that the Justice inherent in the Nature of God, which is the basis for all morality, includes lying, even though God is Truth. The self-contradictory nature of this position on lying, and the way that is dissolved the Faith into nothing, shows that the position is false. We cannot hold that lying is sometimes moral.
Suppose a Pope were to teach that lying is sometimes moral. Immediately all assertions by all past, present, and future Popes would be cast into doubt. We could not trust our salvation to the Church in that case. Souls would be lost by the millions.
So then we are left with the above third hypothetical case again, that of secret teachings. In order to claim that lying is sometimes moral, we would have to claim that the Pope holds to certain secret teachings, which he knows but can’t say. This type of duality in religious belief (public versus secret teachings) is typical of the heresy of Gnosticism and the false religion of Freemasons (masonry). They believe in secret teachings. Christians do not. Instead, we shout it from the rooftops. There is no truth on the subject of faith, morals, or salvation that the Pope keeps a secret.
If lying is sometimes moral, then the Christian Faith loses its surety, since Jesus, or the Apostles, or the authors of Scripture, or the Popes, or the Bishops, could be lying.
And there is no use claiming that lying is only moral in dire circumstances, such as to save innocent lives. For saving souls is more important than saving lives. So if it is moral to lie to save lives, then it would be moral for the Church, the Pope, and the Bishops to lie to save souls.
Suppose that your parish priest tells you, from the pulpit, that lying is sometimes moral. You could no longer trust anything he said. If he says that he will keep the seal of the confessional, how do you know that he is not lying? If he tells you that he has kept the seal of the confessional in your case, how do you know he isn’t lying? If he says that lying would not be moral in the case of the seal of the confessional, how do you know he isn’t lying? If he say that a Sacrament is valid, or a couple has grounds for an annulment, or a particular act is not a grave sin or not a sin at all, how do you know he isn’t lying? You could no longer trust him. The same would be true for Bishops and Popes.
Now suppose that a Catholic theologian or author or blogger or commentator (anonymous or not), asserts that lying is sometimes moral. You could no longer trust that person as a source on questions that have to do with faith, morals, salvation, or discipline. He or she might be lying.
In fact, lying has a way of undermining every human relationship, not just within the Church, but in family, friendships, work, commerce and any other human interactions. Lying weakens the very fabric of society, family, and religion — just as every other intrinsically evil act does. For all such acts are in conflict with the love of God above all else and the love of neighbor as self. That is why intrinsically evil acts are not only impractical, but also always immoral.
by
Ronald L. Conte Jr.
Roman Catholic theologian and
translator of the Catholic Public Domain Version of the Bible.



That would be great . Would also appreciate if you could tell me where the reference for the John Paul II quote is taken from Thanks.
Ron, this is all true, but sometimes, in this imperfect world, we are faced with difficult decisions where the lesser evil is sometimes the only choice one has. An example, Nazis knock at my door looking for Jews to send to the camps. They ask me if I’m hiding Jews in my basement. I tell them ‘No’, knowing full well the basement is hiding several families.
Pope John Paul II quoting Pope Paul VI: “Though it is true that sometimes it is lawful to tolerate a lesser moral evil in order to avoid a greater evil or in order to promote a greater good, it is never lawful, even for the gravest reasons, to do evil that good may come of it (cf. Rom 3:8) — in other words, to intend directly something which of its very nature contradicts the moral order, and which must therefore be judged unworthy of man, even though the intention is to protect or promote the welfare of an individual, of a family or of society in general.”
[Pope John Paul II, Veritatis Splendor, n. 80; inner quote from Pope Paul VI, Humanae Vitae, n. 14.]
I will write a post specifically addressing the “lying to Nazis to save Jews” scenario.