Although I don’t know all of the facets of what he believes, but it sounds like he may be a Calvinist, or at least influenced by some of the Reformed beliefs. Calvinists do believe that works are ‘part of salvation’ in that the ‘saved person’ will do good works. They use phrases like ‘salvation is by faith
alone, but not by a faith that
is alone’ hence, to be ‘saved’ does not require any works to initiate or maintain – or anything except ‘fiducial faith’ (this is more than mere belief, but rather trust and confidence in Christ alone for salvation. However, this does not equate to the ‘Faith, Hope and Charity’ that we Catholics believe is necessary to be in a state of grace), but once you are ‘saved’ you proceed to do good works (because you have been regenerated) and will indeed persevere unto the end of your life in both faith and at least some good works because of election/predestination (since you are one of the ‘elect’ you
will come to faith, and you
will persevere in faith, so it is still ‘once saved always saved’ because you cannot truly fall away.) If one that appears to profess faith and begin to live the Christian life, but then subsequently (for whatever reason) falls away, it merely shows that such a person was
never ‘saved’ to begin with. Not that they were ‘saved’ or ‘justified’ and in a state of grace and then fell from that grace, as we believe is possible, but that they
never were justified because they believe that justification is for the elect
alone (and once justified you cannot fall from that state, even if it appears that you do for a time).
In short, they do not believe in Mortal sin for those that are justified, but at the same time they do not believe that you will be able to live in what would be habitual Mortal sin if you are indeed ‘saved’; so, in other words, you cannot fall from grace if you were to happen to commit adultery, but such a justified person will not commit adultery (or if he happens to, he will repent and turn from it unlike the reprobate who has no regard in his heart for the law of God). Basically, everything is turned around on its head because of how they understand predestination/election and justification/salvation which, in their theology, flows directly from those doctrines.
It also should be noted, that Calvinists do not believe that justification occurs in Baptism or that your sins are washed away by Baptism, but rather the moment you possess ‘fiducial faith’ is when this happens (like most Protestants, they believe that the Sacraments do not effectuate Habitual Grace). So, when you speak of the Sacraments and justification/saved/salvation he will probably have a different understanding of how this is effectuated.
As far as what you should do:
I would ask him what he thinks that John 15 means:
“Every branch of mine that bears no fruit, he takes away… If a man does not abide in me, he is cast forth as a branch and withers; and the branches are gathered, thrown into the fire and burned… If you keep my commandments, you will abide in my love, just as I have kept my Father’s commandments and abide in his love…” etc… Here our Lord clearly says that those branches that do not bear fruit are ‘taken away… and burned’ (the question is, how are they ‘taken away’ if they were ‘never there’ – never ‘in Christ’ to begin with? Also, He gives the conditions for ‘abiding in my love’ and that is to ‘keep my commandments.’
Hebrews 10:
“For if we sin deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins, 27 but a fearful prospect of judgment, and a fury of fire which will consume the adversaries. 28 A man who has violated the law of Moses dies without mercy at the testimony of two or three witnesses.29 How much worse punishment do you think will be deserved by the man who has spurned the Son of God, and profaned the blood of the covenant by which he was sanctified, and outraged the Spirit of grace?” Remind him that those who are not Christians are not sanctified in any way by the ‘blood of the covenant’ yet clearly it is talking here about someone that has been ‘sanctified by the blood of the covenant’ and yet fallen away through ‘sinning deliberately’, it is not saying that this person was never ‘saved’ in-fact, quite the opposite.
Also, couple of my other favorites is 1 Corinthians 9:24-27 where Paul (the Apostle!) talks about disciplining his body lest he be rejected after preaching to others… 2 Peter 2:20-22: clearly talking about those who have fallen away ‘the sow returning to wallow in the mire’. Also, 1 John 5: where John clearly talks about some sins not being ‘mortal’ or ‘unto death’ and some sin that is ‘mortal’ or ‘unto death.’
Ask him what he thinks these verses mean (and, really, countless others that talk about falling away), and how they fit into his theology if those who fall away were ‘never saved’ because that is not the language used by the Biblical authors. You may also ask him what he believes about Baptism; show him the Scripture passages that talk about Baptism ‘washing away sins’ and also, if he has a respect for history, show him the quotes from the Early Church Fathers that talk about Baptism (there are tons of them). If you can convince him of Baptismal Regeneration (and if he is even remotely systematic in his theology) the rest of the erroneous Reformed doctrines may go out the window pretty fast (because, if we are ‘saved’ in baptism – and if it is impossible to fall away if you are ‘saved’ – then that means that everyone that has been baptized will be obtain final salvation – which no sane person will accept). At least, that is what got me away from Reformed theology and started me on the Catholic road. And, above all, pray for his soul.
P.S. sorry about the rather long winded post!
Pax Domini sit semper tecum!
