I know your past training makes it very hard for you as it requires a significant paradigm shift from what you were taught by your mentors.
However, what does scripture tell you?
(Ephesians 2:1-10)
Once you were dead because of your disobedience and your many sins. You used to live in sin, just like the rest of the world, obeying the devil—the commander of the powers in the unseen world. He is the spirit at work in the hearts of those who refuse to obey God. All of us used to live that way, following the passionate desires and inclinations of our sinful nature. By our very nature we were subject to God’s anger, just like everyone else. But God is so rich in mercy, and he loved us so much, that even though we were dead because of our sins, he gave us life when he raised Christ from the dead. (It is only by God’s grace that you have been saved!) For he raised us from the dead along with Christ and seated us with him in the heavenly realms because we are united with Christ Jesus. So God can point to us in all future ages as examples of the incredible wealth of his grace and kindness toward us, as shown in all he has done for us who are united with Christ Jesus. God saved you by his grace when you believed. And you can’t take credit for this; it is a gift from God. Salvation is not a reward for the good things we have done, so none of us can boast about it. For we are God’s masterpiece. He has created us anew in Christ Jesus, so we can do the good things he planned for us long ago.
(2 Corinthians 5:14-17)
Either way, Christ’s love controls us. Since we believe that Christ died for all, we also believe that we have all died to our old life. He died for everyone so that those who receive his new life will no longer live for themselves. Instead, they will live for Christ, who died and was raised for them. So we have stopped evaluating others from a human point of view. At one time we thought of Christ merely from a human point of view. How differently we know him now! This means that anyone who belongs to Christ has become a new person. The old life is gone; a new life has begun!
Again, Amillenialism is very rational and steeped in scripture. You may not agree with it, but it is dedicated to Godly study of the Bible.
It is called the second birth, not the first resurrection.
I agree that all those currently in Paradise have experienced the first resurrection. They have a permanent incorruptible physical body. The first resurrection is physical, so they have had a physical resurrection like those from the OT raised physically at the Cross.
The Second Birth gives you the quickening out of spiritual death. Something you seem to not attribute to those in the OT.
Those in Christ no longer face death spiritually nor physically. Once they leave Adam's corruptible physical body, they leave death behind and enter eternal life.
Dr. Riddlebarger is confused thinking there is still a future single resurrection. So still a futurist in application of his wrong interpretation of the first resurrection. What is this future physical resurrection, the second resurrection?
The first birth was physical, the first death is physical, and the first resurrection is physical.
The second birth is spiritual, the second death is spiritual separation in the LOF. The second resurrection would be out of the LOF.
This false teaching that the first resurrection equates to the second birth is not Scriptural, but human doctrine forced into the Scripture which sounds good, but not logical.
John 3:5-7
"Jesus answered, Verily, verily, I say unto thee, Except a man be born of water (physical) and of the Spirit (spiritual), he cannot enter into the kingdom of God. That which is born of the flesh is flesh (physical) ; and that which is born of the Spirit is spirit (spiritual). Marvel not that I said unto thee, Ye must be born again."
The physical birth comes first. One cannot be saved if one does not even exist.
Paul was speaking about being quickened spiritually. That is the second birth. Paul was speaking about being in heavenly places physically. That is the first resurrection.
Amil tend to dismiss this verse that starts the whole 5th chapter of 2 Corinthians, setting the theme:
"For we know that if our earthly house of this tabernacle were dissolved, we have a building of God, an house not made with hands, eternal in the heavens."
When the soul of those in Christ leaves Adam's dead corruptible flesh, that soul immediately enters God's permanent incorruptible physical body. There is no eternal waiting for this body at some future resurrection. There is eternal enjoyment, because no one in Christ tastes death. The second birth ensures we leave death and enter life immediately.
Jesus was the Resurrection and the Life prior to the Cross. The Cross and Resurrection always being the moment God shows His love towards us, but the power was always there. Jesus is not the "someday there will be a future resurrection and a future life".
Amil is also steeped in human theology, with an emphasis on "human".