Part 2: Presumption
So, your housemate says that one is “guaranteed” salvation by our faith alone?
This is where the presumption part comes into play. Paul tells us: “Can you not realize that the unholy will not fall heir to the kingdom of God? Do not deceive yourselves. . .” (1 Cor. 6:9) and “What I do is discipline my own body and master it, for fear that after having preached to others I myself should be rejected” (1 Cor. 9:27) and “Let anyone who thinks he is standing upright watch out lest he fall!” (1 Cor. 10:12).
The point being–contrary to your housemate’s theology–we CAN fall. We CAN lose our salvation. This is why we read in ROMANS:
“You will say, ‘Branches were cut off that I might be grafted in.’ Well and good. They were cut off because of unbelief and you are there because of faith. Do not be haughty on that account, but fearful. If God did not spare the natural branches, he will certainly not spare you. Consider the kindness and the severity of God–severity toward those who fell, kindness toward you, provided you remain in his kindness; if you do not, you too will be cut off.” (Romans 11:19-22)
Here, St. Paul is very clear. Yes, some (the Gentiles especially) are grafted into the Church because of their belief apart from works of the law (which is entirely different from the “works” James is speaking of, by the way). Yet, these same people who are now “grafted in” because of faith are warned not to be haughy, but FEARFUL as they, too, can fall from God’s grace and be cut off.
“So then, my dearly beloved, obedient as always to my urging, work with anxious concern to achieve your salvation. . .” (Philippians 2:12)
That does not seem very assured to me.
“Be solicitous to make your call and election permanent, brothers; surely those who do so will never be lost.” (1 Peter 1:10)
Here, St. Peter instructs the Church to be “solicitous” in making their “call and election permanent.” That is, it is not already PERMANENT. He is speaking here to Christians. People who believe in Christ. People who have faith. Yet, they are called to be careful in their Christian walk so that they will not be lost. He would not have given this warning if it were not possible to be lost.
“Thus do I hope that I may arrive at resurrection from the dead. It is not that I have reached it yet, or have already finished my course; but I am racing to grasp the prize if possible, since I have been grasped by Christ (Jesus). Brothers, I do not think of myself as having reached the finish line.” (Philippians 3:11-13)
Here, St. Paul speaks so well about how we are to view our salvation. It is a process. It is a journey. We have not already achieved it, so obviously we can lose it. Christ’s sacrifice has won for us the rewards of eternal life, but while we are here on earth we are still on a journey towards him. We have not finished the race, nor should we behave as though we have.
Let us know if you need any more reinforcement–there’s a LOT more.