Although Christians often speak of “Judeo-Christian” ethics and morality, although many Christians seriously believe that Christianity is merely “Judaism with Jesus”, the example of lying to the Nazi in order to not reveal where the Jews are hidden, is an excellent example to show just how conceptually different Judaism is from Catholicism.
Catholicism is a dogmatic religion which deals with absolutes, in Catholicism there is one true religion, one way to salvation. All abortions are murder. All lying is a sin.
In Catholicism, the Hellenistic principle of the responsibility of the individual to oneself is also found.
Taking there concepts together it is deemed that if the Catholic lies to the Nazi and says he does not know where the Jews are hidden, then he has committed a sin. If he doesn’t lie and doesn’t sin but reveals the hiding place of the Jews, the Catholic also bears no personal responsibility for the fact that the Nazi will murder the Jews. This is an act of the individual Nazi and the Catholic has no wish for it to occur and therefore bears no responsibility whatsoever for the murder of the Jews.
Judaism on the other hand is an intellectual religion which demands questioning and reasoning. In Judaism we can not place all acts of lying in all situations as being equal. We must consider overlying principles. The major principle in our example is the absolute supremacy of the the principle of the sanctity of life or "Pikuach Nefesh (פיקוח נפש) - This principle is so valued in Judaism it over rides all of Torah with a few extreme exceptions (for instance murder, idolatry)
The second thing is the anti-Hellenistic, underlying principle in Judaism, that we all have responsibility to our fellow man. In Judaism, an individual who brings about the deaths of those in hiding by revealing their hiding places, carries responsibility for their deaths.
So while the Catholic will argue that if he lies to the Nazi he is committing a sin, in Judaism, a person who does not lie to the Nazi and reveals where the individuals are hiding, is the one committing the sin.