+Peter never stopped believing in Christ, nor did he ever curse God. There is a slight difference there, counselor.
My point is, from the Calvinist perspective, "why does it matter?" Peter's denial of Christ was only what God wanted him to do. Just as Judas' betrayal of Christ was obeying God's will. Just as Pontius Pilate and the Pharaoh were doing God's work and, ultimately -- to reiterate the belief held by Judaism -- that satan is but God's obedient servant which, by necessity, Calvinism must admit too.
It doesn't matter, because regardless which role you play in this "plan" you keep brining up, all the actors on the stage of this world are God's obedient servants, whether they be villains or heroes. All are God's chosen one way or another.
Which begs the question: why pray, why repent; why redeem; why save? Your prayers could not possibly be of hep, because you say God doesn't change His mind; he sealed everyone's fate from the beginning. Your repentance is spiritually void because you say that whatever you do is simply because it's God's will. Our redemption is unnecessary because we never sinned; we simply obeyed God. We don't need to be saved, because we did not sin; we only did and do and will do what God and no one else pre-ordained to be done.
If everything is is God's will, lest we "thwart God," then nothing is our will. If nothing is our will, then we are always slaves to righteousness, since either way is God's will, and His will is always righteous and just.
That is what the scriptures states.
Which begs the question: why pray, why repent; why redeem; why save?
It is precisely because salvation is from the Lord that we can pray for the salvation of others. If man has God given free will then there is no point in praying. God will not intervene in a person's free choice. Consequently, you can't pray for Sam's salvation simply because Sam is exercising his divine right.
When one stops and think about prayer, it is a great mystery for God's knows all our needs, takes care and watches over us, etc and then ask us to pray for things. The only thing I can tell you about prayer is that it helps us to know God's will. If you pray for something and regardless if your prayer is answered or not, you know what is God's will. God answers our prayers (or not answers them) to show us His will.
Your repentance is spiritually void because you say that whatever you do is simply because it's God's will.
Our repentance is not void. We repent because God brings us to a point of repentance.
Our redemption is unnecessary because we never sinned; we simply obeyed God.
I believe I'm on record to say man does sin, even after becoming a Christian. Christians just don't practice sin.
If everything is of God's will, lest we "thwart God," then nothing is our will.
We don't "thwart" God. God "thwarts" us.