I believe I see the distinction between your OSAS teaching and that of others, which I have not been given before.
Well, not to offend, but that has been painfully obvious. :)
Unconditional OSAS declares we have already gotten the crown and prize at the start of the race by faith alone. It's a done deal no matter how the race is run.
Agreed. As I said, that is the heresy of antinomianism, that there are no longer any consequences of sin. And Paul is very clear in his refutation of such an understanding in Romans 6, where he says, "What then? Are we to sin because we are not under law but under grace? By no means!"
Your OSAS acknowledges the race must be run lawfully first to obtain the crown...
Well, our having been given the mercy of God and born again of the Spirit demands our responsibility to live lives becoming a Christian and running the race (Hebrews 12:2), sure. But there is sort of a "freedom to fail," in the sense that we will not in this life run that race perfectly, that we will fail to do so perfectly, that we will still sin in this life ~ we still fall short of the glory of God ~ but still there is
no more condemnation of us who are in Christ as a result of not running the race, failing to run the race perfectly, sinning, or falling short of God's glory.
...the assurance you teach is that you certainly will do so? And so, the obvious question is: are you saying there is no chance of not doing so? I.e. yes, we must first run the race, but doing so to the end is as a done deal? Or is running the race to the end conditioned on how we run it?
Well, if your focus is solely on
us ~ which it seems to be ~ the answer is
no. In and of ourselves, it would actually be a certainty that we would
not do so.
But since God is at work in us, He's the one Who makes it a certainty:
He has given us a new heart, and a new spirit He has put within us; He has removed the heart of stone from our flesh and given us a heart of flesh, and He has put His Spirit within us, and causes us to walk in His statutes and be careful to obey His rules. (Ezekiel 36:26-27)
"He has made us alive together with Christ ... we are his workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them." (Ephesians 2:4-10)
So... and this should not be "mysterious"...
no, with regard to ourselves only,
but yes, with regard go God. As Paul exhorts us all, as Christians, we should all work out our own salvation with fear and trembling, for it is God who works in us, so that we then will and work for His good pleasure (Philippians 2:12-13). And Paul tells us this just after he has told us, in Philippians 1:6, "I am sure of this, that He who began a good work in you will bring it to completion at the day of Jesus Christ."
.. and yes. :)
What of those who turn back to sin and forsake his cross?
Ah, well those... Here's what the apostle John tells us about them:
"They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us. But you have been anointed by the Holy One, and you all have knowledge." (1 John 2:19-20)
So, those who turn back to sin and forsake his cross were never really Christians in the first place; God never began His good work in them, else they would not have turned back to sin and forsaken His cross. Notice there that he's contrasting between us and them and saying that we have been anointed by the Holy One, and the strong implication there is that they have not been. You see?
Grace and peace to you, Robert.