Well, I believe salation is a free gift as stated:
5:15 But not as the offence, so also is the free gift. For if through the offence of one many be dead, much more the grace of God, and the gift by grace, which is by one man, Jesus Christ, hath abounded unto many.
5:16 And not as it was by one that sinned, so is the gift: for the judgment was by one to condemnation, but the free gift is of many offences unto justification.
5:17 For if by one man's offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ.) 5:18 Therefore as by the offence 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.
5:19 For as by one man's disobedience many were made sinners, so by the obedience of one shall many be made righteous.
(King James Bible, Romans)
Now, salvation above is free, paid for by Christ, see how many times free, and free gift are mentioned in bold. Also, look at this:
4:3 For what saith the scripture? Abraham believed God, and it was counted unto him for righteousness.
4:4 Now to him that worketh is the reward not reckoned of grace, but of debt.
4:5 But to him that worketh not, but believeth on him that justifieth the ungodly, his faith is counted for righteousness.
4:6 Even as David also describeth the blessedness of the man, unto whom God imputeth righteousness without works, 4:7 Saying, Blessed are they whose iniquities are forgiven, and whose sins are covered.
4:8 Blessed is the man to whom the Lord will not impute sin.
Here we see, that salvation is a gift, if we try to work for it, it is no longer a gift, but a debt, and God will not be a debtor to anyone. Works are a RESULT of our salvation, not something we DO to earn or KEEP it.
Having said that, we know as it also says in Romans, "Shall we sin that grace may abound? God forbid." So, I believe, we are saved as a totaly free gift, that works will be an evidence of this, and that as Christians we should, and actually will strive to keep Christ's commandments. For as many as he loves, (his children), he corrects, or chastiseth. The Holy Spirit is now working in us, teaching and leading us to be more like Christ, we still have our sin-nature, but we are also born-again, new creations, in Christ, who keeps us, who is our advocate, who will in no wise cast us out. So, I believe we are freely saved, when we trust in Christ, and we grow IN the grace of Christ, AS His children, always His children, not always in fellowship, but always in relationship, some of us grow faster than others, some will receive more reward than others, some travel around that same old mountain, that same old sin, habit, etc., and it can make them unfruitful, or less fruitful, and even cause pain, sickness, death, for them and others, yet their salvation is secure, as it is a free gift, it is the one thing we cannot do anything to earn. Hope that clarifies my view a bit. Thanks.
Mike