UNTIL the second resurrection when we read that they will be the only raised up to stand for judgment. There is NOTHIING "blessed and holy" about the Second Resurrection!
There is no second resurrection. That is an imagined assumption. It would still be the first resurrection for those still in their graves.
There is a negative point made by John here:
"But the rest of the dead
lived not again until the thousand years were finished."
Those beheaded lived not again until they stood in Judgment. The first resurrection is living again. Those physically dead can only be resurrected once. That is the first / physical resurrection.
Those beheaded were not alive until given a permanent incorruptible physical body. That was the Judgment awarded them. What redeemed person has to stand and be judged before they can be redeemed and given physical life?
You are assuming those beheaded were redeemed prior to being beheaded. That is not the case. If that were true they would not be standing in Judgment waiting for redemption.
Even if you falsely allege the first resurrection is merely spiritual, those beheaded were not "spiritually resurrected" (your alleged first resurrection) until they stood in Judgment.
It is not inherent in Revelation 20 that there is a chronological first resurrection followed by a second resurrection. Nor is it implied that one is to eternal life and the other is not to eternal life. The first resurrection is awarded to those made alive at either Judgment.
John could have written:
"They lived and reigned with Christ a thousand years. This is the first resurrection. But the rest of the dead lived not again until the thousand years were finished. This is the second resurrection. Blessed and holy is he that hath part in either resurrection: on such the second death hath no power, but they shall be priests of God and of Christ, and shall reign with him forever."
But he did not!
The resurrection outcome is still the same each time. What could happen is both groups could receive the spiritual birth for the first time and a physical body for eternal life. Why?
Because both were in a spiritual and physical state of death. The only difference is one group was physically beheaded for an explicit reason, and the other group was simply dead. It assumed that all in the first group were awarded eternal life, while all in the second group was awarded the LOF. Except the second group could live again, if that was the outcome of the Judgment handed down. It is assumed the majority would not live again.
"the rest of the dead lived not again"
"Living again" is how you use the first resurrection as defined to be a spiritual birth. Otherwise you could call neither judgment, one that gives spiritual life. If they had had a spiritual birth they would not be "the dead".
So how can you say the first resurrection takes place both prior to physical death and after physical death? You would not be able to use either first or second as qualifiers for your resurrection, as the whole point is that these people in both cases needed a physical resurrection equally.
And in both cases since they were physically dead, and many since before the Flood, they also needed a spiritual birth, as they all were spiritually dead as well.
That is the reason why there were 2 different times this resurrection was applicable. That is why there is a negative connotation, instead of a positive connotation regarded living again. They all were physically dead in both cases. They all needed a physical resurrection. They all needed both a spiritual birth and a physical resurrection. Both could not be spiritually alive, because they all, in both instances, needed the same set of circumstances: facing judgment and waiting for a sentence handed down to them. But the spiritual should never be called a resurrection. It is always the second birth. The spiritual is called the second birth whether they are physically dead or not.
One does not need either to be tossed into the LOF.
I did not respond to your whole post, because your conclusion that the first resurrection is not physical makes no sense. You are declaring that neither the first resurrection nor the second resurrection are physically eternal life. So there is never a physical resurrection at all that you can even call a resurrection but something else other than a resurrection as you say, "will be only raised up to stand for judgment". Well those beheaded were only raised up to stand in judgment, so that was not a first resurrection either then according to you, but a second resurrection, the first time, where the other group has to wait until a later time to stand in judgment. Both groups stood in Judgment after physical death. All of the first group received redemption at that Judgment. At the second Judgment some could receive redemption, but others will not, because both events claim those "raised" cannot have the resurrection of life (the first resurrection) until after they are judged. Not that they need life to be judged.
You are using two specified events with time in-between to create a doctrine called the "first resurrection" where both events have the dead standing in Judgment. One group was beheaded the other group dead from all types of causes, over a 6,000+ year time frame. Yet you call one good, and the other bad per a chronological order. The only thing "good" about the first group was that they were beheaded, not because they had the second birth nor the "first resurrection" while alive.
John never once in Revelation 20 claimed to see people in physical bodies standing in Judgment, nor that they even needed a body to be judged. He saw souls and the dead implying they have no physical bodies, until they were judged and awarded a first resurrection with a physical body, and an assumed second birth, both states awarded after they were judged, preventing them from the second death, which was the action of being tossed into the LOF. The majority of the dead did not live again, but were cast into the LOF, never receiving the first resurrection nor the second birth.
The first resurrection applying to the fact they could live again, which is not a birth, but a resurrection of the physical body. The second birth does not place one into a spiritual body. The second birth makes you a son of God guaranteed a different physical body that is of God (spiritual) permanent and incorruptible.