Can someone who rejects the Catholic church and yet believes in Jesus be saved?
Those who have know the Catholic Church as the true Church yet knowingly refuse to persevere in her will not be saved.
Now, you may ask, "But what if they believe in Jesus and yet knowingly refuse to persevere in the Catholic Church?"
Answer: By rejecting the Catholic Church after knowing her as the true Church shows that you don't believe in Jesus, in what He said, in what He did, and in what He willed.
Belief in Jesus and in the Catholic Church as His Church go togetherm hand in hand. If you knowingly, purposefully, and freely reject one, you reject the other.
In Christ,
P.