At the heart of the debate over the permanence of the bride’s salvation is a typical spiritual error—lifting verses out of their contexts. So, not understanding what salvation actually is, or to whom particular passages of scripture refer, many in christianity conflate things written about justification (salvation), with passages concerning sanctification (the sacrifice of the flesh encouraged of those who already are saved).
If salvation comes by way of man’s decision, prayer, or lifestyle change, then it can go away just as easily, since man is flawed, and doesn’t have the power to save. That which is decreed by the Father cannot be altered by man—and justification is an eternal judicial decree of adoption by the Almighty.
Consider this: in human adoption, who decides an adoption is going to occur? Does the child make that decision, or does the adoptive parent make that decision? There is no difference in the spiritual adoption that occurs with salvation. Yah decides to whom His Holy Spirit (the Covenant) will be given, and when. To claim otherwise is to put man in the Creator’s position of authority and power. Obviously, such a salvation is false, and derived from a false gospel.
So, the only way this debate is proper is first to correctly define what salvation even is. Often, in the “church,” that is not even the starting point, as most don’t really know what justification actually is, how it occurs, or how one knows he has received it. When one understands all that, then there really is no debate at all.
For more information: Once Saved Always Saved?