So any of us who are discussing this are not obedient Catholics?

I did mention earlier that I have relatives who buy in to this notion - btw, they are not Calvinists, Baptists or of Reformed church. How could I not want to understand it more so that I could have a discussion with them about it at some point? I certainly don’t believe in what I know of it as it does not make sense to me and isn’t biblical as far as I can see.
Again I am wondering if anyone can explain it clearly …OSAS - does that mean that once you are saved (believe in Jesus as your savior and Lord and accept his death as your salvation) can you do anything you want (sin) and it is automatically forgiven?
I wasn’t trying to put you on the defensive or stop you from talking about it, but to state very clearly for those who do not hold to church teaching that this is a non-negotiable.
Proponents of OSAS maintain that once you have a conversion experience to Christ you gain a ticket to heaven (to put it crassly.) According to them, there is nothing you can do to lose this ticket, just as there was nothing you could have done to earn this ticket. Your salvation therefore is not contingent on any earthly behavior, either positive or negative. This means that you can sin at will, however no Calvinist worth his salt would ever encourage sinful behavior.
In order to more fully understand this Calvinist mindset one must realize that Calvinists believe humans are inherently evil from the fall. This means that one cannot perform a good work even if one desires. Man is only capable of evil thoughts and works because he is utterly depraved. Any good works that occur is The Holy Spirit doing good works through you. This includes the acceptance of salvation in the first place because man is incapable of accepting salvation. In other words, there is no participation on the part of man whatsoever. Because you could not have accepted this gift of salvation without the Holy Spirit accepting for you, you likewise cannot do anything to merit keeping this salvation, even if you blatantly reject Christ at a later time. (Calvinists would argue that someone who did this was probably never saved to begin with…more on this in a sec.)
This has also led Calvinists to believe that God selected (before time began) who would go to Heaven and who would go to Hell and this decision is finalized and there is nothing anyone can do about it.
Calvinists would see those who people would describe as backslidden or fallen away as having never been saved in the first place i.e. they were just faking being a Christian and finally showed their true colors.
Calvin additionally thought there were signs to be able to identify those who were predestined to salvation, one of which was worldly prosperity. He maintained that those who were saved (from before all time) would experience relative comfort in life and those who were destined to Hell would experience relative suffering.
Calvinists would say that although works are not necessary in the least for salvation, those who are saved should naturally tend to good works because of the infusion of the Holy Spirit. They do however believe that the works simply follow as a natural companion to faith but that the works have nothing to do with salvation.
None of this is Church teaching you understand and they are the hallmark teachings of Evangelical Protestants aka Calvinists (Baptists, Presbyterians, and others). In fact these are heretical teachings and they have been formally condemned by the Church. In fact, these particular teachings were even condemned by Martin Luther who maintained until his death that John Calvin would burn in the fires of Hell, a courtesy returned by Calvin who maintained that Luther would be the one to burn.