Coming from a Protestant and distinctly Western (i.e. juridical) view of salvation, I have to wonder if this isn't perhaps parsing terms and words a little fine. If there is anything that we must do to obtain or maintain salvation, then it has ceased to be grace, that is, sheer unmerited favor from God. When the Roman Catholic Church states that if you miss a single Mass, you no longer have salvation, please explain to me how that is not putting works as part of the salvific process? It is this kind of thinking, along with the extreme legal salvific minutiae which border on superstition (such as observing Five First Fridays or saying the 15 Promises of the Daily Rosary) which appear to any thoughtful person as being salvation by works. In other words, you do so many works (prayers, Rosaries, First Fridays, First Saturdays, etc) and BINGO!!! you got the guarantee. Now if that ain't works, I don't know what it is!! In other words, if it has ANYTHING to do with eternal life with Christ as the ultimate destination of the soul, then it is part of salvation, isn't it? This is a real recipe for despair, as Luther found out, for when does the conscience rest satisfied that enough works have been done to have that personal guarantee of eternal life? Anyone with even the slightest internal knowledge of their own weaknesses and failures cannot help but feel a certain despair and fear of the Judgment Seat, lest they be found wanting and sent into the eternal torment Rome promises to the sinful.
Now I am going to throw a real monkey wrench in the works. St. Paul is rather clear in Romans 5 that salvation has been given to all mankind - that is, all people who have or ever will live.
Rom 5:18 Therefore as by the offense of one judgment came upon all men to condemnation; even so by the righteousness of one the free gift came upon all men unto justification of life.
Rom 5:19 For as by one man's disobedience many all were made sinners, so by the obedience of one shall many all be made righteous. (The disobedience of one made ALL MEN sinners. I don't know where the translators came up with this idea!!! This also corresponds with verse 18)
But....but....but....what of the Judgment Seat of Christ? Does not the Bible itself promise a Judgment?
Perhaps the Roman Courtroom view of God has given us a presupposition of the Last Judgment which is completely out of line with grace and the teaching of the Scriptures. In the East, we view salvation as medicine, not courtroom. The Judgment Seat of Christ is for two purposes (this is my opinion, for what it is worth):
1. Determination of the ontological status of the soul and what needs to be done with it to heal it. In this life, we have the opportunity to cooperate with the Holy Spirit and thus enable the process of theosis. Theosis is the healing of our soul, the return to the original plan of God, the goal for which we were created. Rather than thinking of the Judgment Seat as a place of juridical condemnation, the West needs to think of it as the place of medicinal judgment. What is lacking and what needs to be done to finish the healing of the soul standing before Christ? The love of God in Christ will heal all souls. The more wicked the soul, the more it will be torment (St. Isaac the Syrian - "The love of God is experienced as torment by the sinner"). The goal is restoration, not condemnation.
2. Determination of reward in the ages upon ages. Do you really think that I, wretched sinner that I am, shall have the same reward as St. Nektarios, St. Pophirios, or the other ascetics of Mount Athos? Will I have an equal reward to those valiant soldiers of Christ - the martyrs - who counted their lives as dross in order to obtain the Pearl of Great Price!
HA!! You joke!!
Christ offers the world with His gracious words "Come and follow Me." the opportunity to amass treasure in heaven (Matthew 19:21). Will those who disregard the call have treasure? Will those who not only disregard the call, but pursue earthly pleasures have treasure, or chastening? The Judgment Seat of Christ will sort this all out, and standing in the place of truth in front of He who IS Truth, all will be made clear
Perhaps this is why the Roman Catholic Church has been hemorrhaging members for a long time. People are tired of a message which is condemnatory and discouraging. For those who are truly serious and truly thoughtful about what is being taught, the bar is set too high, the stakes are too terrible to think of, the whole thing is simply not encouraging. Protestantism, on the other hand, sets the bar way too low, allowing for the entrance of all manner of wickedness under the guise of "grace," and lapsing into antinomianism. Only in Eastern theology have I found the balance which encourages me to press on - not towards judgment, but towards love. Not towards a God who stands ready to condemn me for the slightest infraction, but to my heavenly Father who stands ready to both encourage me and heal me through the ascetic exercises given to me - given not to earn, keep, or continue in salvation, but to heal me from me sin and make me a true son of God.