From my book: Forgiveness and Salvation for Everyone —
Can a Jew, who is well aware of Christianity and its teachings and who does not choose to believe in Jesus Christ, possibly die in a state of grace and be saved? Yes, this is possible. Since the time of Christ, many Jews have died in a state of grace and were given eternal life in Heaven. For whenever an objectively grave sin is committed — such as rejecting Christ and His Church — but without full knowledge or full deliberation, the sin is not an actual mortal sin. And only actual mortal sin causes the loss of the state of grace and deserves eternal punishment in Hell.
The refusal to believe in Jesus Christ as the Messiah is objectively wrong. However, it may not be an actual mortal sin, if the person who refuses to believe is sincere in seeking religious and moral truth, and yet does not believe Jesus is the Messiah. How can a sincere adult, who has the full use of his faculties of reason and free will, not perceive that Jesus is the Son of God and Savior of the world? One reason is that so many Christians, especially Catholic Christians, fail, very substantially, to live according to the teachings of Christ. They obscure the goodness and truth of His teachings by not living them well, by their many sins and failings, including mortal sin. Another reason is that the world is sinful and offers a wide variety of erroneous opinions on every matter of faith and morals. It is more difficult to perceive truths pertaining to salvation in such a circumstance.
Pope John Paul II: “For those too who through no fault of their own do not know Christ and are not recognized as Christians, the divine plan has provided a way of salvation. As we read in the Council’s Decree Ad Gentes, we believe that ‘God in ways known to himself can lead those inculpably ignorant of the Gospel’ to the faith necessary for salvation.”
The strongest case for someone to be inculpably (blamelessly) ignorant of the Gospel of Christ is found in those human persons who lived before Christ. They are not guilty for their ignorance of the Gospel before it was preached. But a good case can also be made for invincible ignorance, or at least a substantial reduction in culpability, for Jews and others who lived after the time of Christ. They may have known of the Gospel in the sense of knowing about Christ, His Church, and Christian teachings. But they might not know that rejecting Christ and Christianity is gravely immoral. So they are, in that sense, ignorant, and therefore still able to walk the path of salvation.
They can be saved by Christ, despite outwardly rejecting Him, if they accept Christ implicitly, by the love of God through the Jewish religion and by the love of neighbor. A substantial reduction in the culpability of rejecting the Christian Faith results from a lack of knowledge of the grave immorality of that choice, which results in this objective mortal sin being reduced to an actual venial sin (or in the idealized case, no sin at all). But invincible ignorance need not be so full that there is no actual sin at all. It is sufficient for salvation that an objective mortal sin be reduced in culpability to that of an actual venial sin. For only actual mortal sin condemns a soul to Hell.
But can a Jew who knows about Christ and yet does not accept Him go to Heaven without any purification in Purgatory? Does he not need to stay at least briefly in Purgatory or its limbo in order to know Christ? It is perhaps the usual case that a Jew who dies without accepting Christ goes to Purgatory, so as to know Christ before entering Heaven. As we have previously discussed, it may be the case that everyone who accepts Christ only implicitly in this life must spend time in Purgatory or its limbo so as to know and accept Christ explicitly before entering Heaven. However, that point is an open question.
Suppose that a Jew who has no actual mortal sin on his conscience dies in an heroic attempt to save the lives of other persons, out of a sincere love of God and love of neighbor. His last act of life is a full cooperation with grace in an act of true spiritual love. Therefore, by that act of full cooperation with grace, he knows Christ, even without accepting His name. This heroic sacrifice suffices to remit all temporal punishment due for sin in his life, and also constitutes an implicit repentance from all sin by implicit perfect contrition. Such a person might avoid Purgatory altogether, and be sent directly to Heaven after meeting Christ in the particular judgment.
Some Jews know Christ implicitly better than many Christians know Him explicitly. For many Christians lead a life of lukewarm love of God and neighbor, and when they die in a state of grace, they still require a long purification in Purgatory. But some of the most devout Jews might require little or no time in Purgatory.
So a comparison between devout Jews and Christians does not always favor the Christians. Of those to whom more is given, more will be expected. A Christian who loves God only lukewarmly fails to a greater extent than a Jew (or a person not raised in any particular religion) who also loves only lukewarmly. The objective rejection of Christianity by Jews who lived after Christ is a grave error. And yet that error might not be an actual mortal sin for many Jews. Thus, they can still be saved, and might even spend little or no time in Purgatory.
God judges each human person according to his or her conscience. And conscience can sometimes err without culpability. For as the Second Vatican Council taught: “Conscience frequently errs from invincible ignorance without losing its dignity.” Therefore, a Jew living subsequent to the time of Christ might decline to convert to Christianity without the culpability of an actual mortal sin. Salvation would then still be available by an implicit baptism of desire. And forgiveness would still be available, if the person sins gravely in any area of life, by perfect contrition.