Question:
Answer:
First off, one is never obliged to tell someone something he has no right to know. On the other hand, we are not permitted to lie. It is sometimes said, “You may never lie, but you do not always have to tell the truth”—meaning, of course, that there are some truths you do not have to reveal.
Instead of a lie, one should use some manner of speaking from which the truth cannot be gleaned but which is not literally a lie. This includes some well-accepted social conventions such as, for example, telling a caller that someone is not in or cannot come to the telephone, meaning that he is not available. This spares the feelings of the caller, who does not have the right to know the reason why in any case.
In the case of extreme danger, when dealing with one who obviously has evil intentions, one may use materially misleading speech, but even then one may not lie. Telling the Communist officials that you do not know where the person they are seeking is is not a lie, since their intentions are unjust and they have no right to know; and there is also a sense in which you do not know exactly where the person is in the context of his hiding place. This case does not apply just because we do not want to expose the person to the law, but only in the case where those seeking him have no right to do so.
Remember also that in such difficult cases, where a person is responding immediately to a complex situation without much forethought, that God will surely not judge our efforts harshly, even if we fail somewhat under pressure. Simply put, a lie of convenience in a gravely difficult situation is most likely a venial sin either in itself or from the lack of freedom engendered by the circumstances.