Both sides of the argument insist that salvation, in terms of ultimately being saved, can only be had through a faith that perseveres. If one lacks this type of faith, if they have a belief in Christ that is fleeting, then is it correct to say that the person is truly saved?I am going to take a contrarian position and argue that we are not once saved, always saved. Now, as this debate dovetails with the debate of whether we have choice or some free aspect of the will, I believe it is and will be shown to be couched in Arminian vs Calvinistic language and arguments.
The following is a very simple argument I will build on in time in this thread. Now, I will be doing bible study as this debate evolves and I will find all the verses I can and post them. This will help me better argue my contrarian position in new ways.
For now I will point out that Believers, whom the New Testament talks to, are regularly called by Jesus and the apostles to watch their behavior. Not only are they told this, but they are warned repeatedly of horrible consequences. Of these consequences, the one that jumps out most especially is eternity in hell. We often assume these verses apply to false Christians, but how do we define a false Christian? Why not just use the rubric that one who does not live doing the Father's will is in fact lost. This would seem to be a great way of making the Gospel message make sense given the hard statements of Matthew 7, the Book of James, and the Book of 1 John. These statements are no longer hard if we believe that we have always had the choice to jettison our faith. Also, how in the world does any of this fit into the conception that a person has all of their sins past, present, and future paid for? The weight of so many warnings should give pause to those that think they are permanently safe.
In addition, the disciples are even told to not judge outsiders but to instead judge amongst themselves and rebuke each other so as to be free of sin. Relatedly, we are told to fear the Lord all throughout the bible, including the New Testament. However, how can we have a healthy fear of the Lord, and thus be deadly afraid of rejecting His will, if we believe ourselves to be eternally safe? Why fear God at that point?
Lastly, if there is no certainty to our salvation in this life, does that mean we have so called free will or that God's plan is more complex than previously believed
Again, I will have the verses to back up my basic assertions and add to my statements in time. I just don't have the time to look all of them up tonight.
Insofar as your argument of Christ paying for our sins – past, present, and future – I agree it is problematic. Christ ceases to truly be Mediator because there is nothing to mediate. But this is due to what I believe to be a flawed idea of atonement.
Instead, I think that the focus on eternal security is whether or not one belongs to the people group Scripture calls “the elect”. If we depart from this group then we never belonged. If we belong, then we will never depart. Why? Because the elect are the people of God, saved by Him, for Him, and in the end preserve by His strength and not their own.