MichaelP mentions that missing Mass amounts to apostasy or at least heresy. Here are the definitons from the Catholic Encyclodedia:
Apostasy is the complete and voluntary abandonment of the
Christian religion, whether the apostate embraces another religion such as Paganism, Judaism,
Mohammedanism, etc., or merely makes profession of Naturalism, Rationalism, etc. The heretic differs from the apostate in that he only denies one or more of the doctrines of revealed religion, whereas the apostate denies the religion itself, a sin which has always been looked upon as one of the most grievous.
Missing Mass does not amount to apostasy or to even heresy. It is, hopefully, until confession, only a temporay state. It is a grave sin and as stated numerous times in previous posts is mortal only when full knowledge and full consent of the will are invovled and will send you to eternal separation from God
IF UNREPENTED.
MichaelP, most Catholics KNOW that missing Mass is grave matter. If a Catholic misses Mass because they just don’t feel up to going, that’s not a good reason. More than likely, that Catholic will feel the pangs of guilt and will probably wish that they had not missed Mass knowing they committed a sin. Now this same Catholic will probably know that he needs to get to confession as soon as possible to re-establish the grace necessary to mend his relationship with God. His plan will probably be to go to confession before the next Mass.
Now, if that person dies in car accident before he can get to confession, God knows his intention was there to go to confession. He more than likely will not experience eternal separation from God since he had contrition for the sin and intended to go to sacramental confession.
If that Catholic missed Mass intentionally (with full knowledge and consent) because he just didn’t feel like going because he didn’t really see the necessity in going; deciding on his own that the 3rd commandment was not worth keeping and did not
intend to confess because he didn’t feel it was a sin or that “surely God would not condemn me to hell just for missing Mass,” well, I’m not sure that he wouldn’t experience that eternal separation. Only God knows his heart and what impediment there was for him to misunderstand God’s 3rd commanment; to think that it was not necessary to keep all God’s commandments.
What we are saying is that all we know is what God’s tells us. If He tells us to “Keep the Sabbath HOLY,” well, that means go to church and worship God - not rest and be with family and play around all day. We don’t know all the things that could keep someone from understanding correctly what that means and what circumstances are playing out in a person’s life - only God knows that.
In the end, it is not God who condemns us to forever be separated from him. It is our choice, when we commit mortal sins and being unrepentent, that separates us from God.