I’m on my phone makes links tricky. Apostasy is clearly defined in the Catechism.
I have a family member who committed apostasy. They were baptized in a valid Christian baptism as a child. They later were baptized Mormon. A complete rejection of Christianity.
Apostasy is simply the rejection of the faith. It can be partial or total.
When one leaves The Church to join a “Christian tradition” not anchored to Peter we commit apostasy albeit a partial one. We pray that the Holy Spirit will guide these souls back to the fold.
If we reject Christianity altogether then that would be the “total apostasy” example.
Peace!
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