The idea that there will still be people in flesh bodies, having children, etc., during Christ's future "thousand years" reign with His elect is a Jewish myth. It's an idea of those who have difficulty understanding that the only... body type of the world to come will be the "spiritual body" Paul taught. That is the body type of the future resurrection Paul showed, and it is not just for those of the 1st resurrection. It will be the body type of the unsaved also. There won't be any marriage, nor having children after Jesus returns.
Thus the Rev.20:5 verse is NOT about the wicked dead being raised after the "thousand years", nor about unsaved dying during the thousand years being raised after the thousand years. When Lord Jesus returns on the last day of this world, the concept of FLESH DEATH will be over and no more.
The Rev.20:5 verse is about a 2nd resurrection of putting on Christ by those preached to all throughout the "thousand years", and they convert to Jesus Christ and thus become "born again", and joined with the 1st resurrection saints after the thousand years, after they are tested by the devil who is loosed one final time after the thousand years.
What kind of idea was Lord Jesus referring with the below?
Matt 23:27
27 Woe unto you, scribes and Pharisees, hypocrites! for ye are like unto whited sepulchres, which indeed appear beautiful outward, but are within full of dead men's bones, and of all uncleanness.
KJV
Luke 11:44
44 Woe unto you, scribes and Pharisees, hypocrites! for ye are as graves which appear not, and the men that walk over them are not aware of them.
KJV
John 3:3
3 Jesus answered and said unto him, Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God.
KJV
John 3:5-6
5 Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
6 That which is born of the flesh is flesh; and that which is born of the Spirit is spirit.
KJV
Lord Jesus in the above revealed His Salvation is to our 'spirit' by The Holy Spirit, not with a new flesh body. He showed those scribes and Pharisees against Him were 'spiritually dead' inside their flesh, even while they were yet alive walking around. It relates to the "second death" of one's spirit with soul at the final Judgment. During the future "thousand years", that "second death" is the only type of death that will remain. Flesh death will no longer exist after Christ's return.
Apostle Paul revealed this in the Greek of 1 Corinthians 15:53-54 with 4 different Greek words with 4 different meanings. Just as how it is today with man in flesh bodies, some of us have been "born again" by Faith on Jesus Christ, while others are spiritually dead for not having been "born again", meaning their 'spirit' by The Holy Spirit. Paul showed the mortal souls of the resurrected wicked will still be in a 'liable to die' condition, subject to the "second death". We all will manifest with the "spiritual body", but not all souls will be made immortal. Only those of the 1st resurrection when Jesus comes will have their souls made immortal. However, we ALL, the unsaved too, will manifest with the "spiritual body". Many preachers make the mistake of thinking that only those of Christ's Church will be given the "spiritual body". They do not heed what Paul taught in those 53-54 verses that it will be the condition of one's soul that will determine whether they perish or not. The "spiritual body" is simply a body type for manifesting in the heavenly dimension. It does not mean automatic Salvation in Christ.