Question:
Answer:
Not necessarily. In fact, you might come to know Christ first as a Protestant and then come into full communion with the Catholic Church, building on your initial Christian faith. There are many examples in recent years here in America, including the conversions of prominent theologians and converts Scott Hahn and David Anders.
If you begin as a Catholic and then become a Protestant, that is more perilous, because then you are moving away from the fullness of Christian truth. Even if you don’t become an atheist, you could be eternally lost if you commit mortal sin in leaving the Catholic Church and failed to repent of it (see the Catechism of the Catholic Church 846-48).
If you reject your Catholic faith heritage, you are more vulnerable to atheism, insofar as you are rejecting Christ and his Church to one extent or another. Something will have to fill that vacuum of authority, and that could be a Christianity reformed according to your own preferences. And once that process begins, you could progress to exalting yourself over any external authority and possibly become an atheist.
Meanwhile, there are many Protestants who love the Lord. Let us pray that in walking with him they come into full communion with Christ’s Church.