I did a precursory search on google to see if there were any other threads about doubt on Catholic Answers forums, and there were, only they said involuntary doubt wasn’t a sin. This is not what the catechism says:
2088 The first commandment requires us to nourish and protect our faith with prudence and vigilance, and to reject everything that is opposed to it. There are various ways of sinning against faith:
Voluntary doubt about the faith disregards or refuses to hold as true what God has revealed and the Church proposes for belief. Involuntary doubt refers to hesitation in believing, difficulty in overcoming objections connected with the faith, or also anxiety aroused by its obscurity. If deliberately cultivated doubt can lead to spiritual blindness.
Involuntary doubt is a way to “sin against faith.” Now, this bothers me. First of all, it sounds like the Catholic Church is teaching we should believe without caution–but what about that Bible verse that says “test everything; hold fast to what is good” (1 Thes. 5.21)? It is referring to “prophecies” specifically, but some of those prophecies might be God’s revelation or something the Church proposes for belief, moral or intellectual. What’s going on here?
Is involuntary doubt a sin or not?