Is abandoning Catholicism a mortal sin?

I was wondering is abandoning Catholicism a mortal sin? A few relatives and I am sure a few friends of mine have left the Catholic Church.

These links should explain the effects on one’s salvation when choosing to leave the Church. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.

Recommended Reading:
Protestants and Salvation

Can you help a former Catholic?

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