I have a question about Catholic theology that I have been wondering about for some time. I am asking only out of idle curiosity and not out of any fear that the fate of my soul may depend on the answer or anything, so hopefully we can all be respectful of each other and keep this out of GD.
I have the following two beliefs about Catholic theology, which appear to contradict each other, so either one must be wrong or there is some clever Jesuitical way of reconciling them:
Once you are baptized into the Catholic church, you are forever Catholic in the eyes of the Church; you can never become a non-Catholic, you can just choose to become a bad Catholic.
Part of the Vatican II reforms were to discard the doctrine of “supersessionism”, which held that the coming of Jesus invalidated God’s covenant with the Jews and thus made Judaism irrelevant. Thus, the Church now believes that Judaism and Catholicism are equally valid approaches to God and both capable of bringing salvation to their believers.
SO… what happens if someone decides to convert from Catholicism to Judaism? Is the Church OK with that? Does it matter if the conversion is to Orthodox Judaism as opposed to some liberal variant? How about if the party involved was baptized but never had any religious teaching or involvement with the Church after that (say, if an infant was orphaned just after baptism and adopted by a Jewish family?).
Again, I am really just interested in knowing what the Church’s take is on this and not in debating the merits of its position.