Revelation is referring to the spiritually, not the physically, dead. Paul before the sanhedrin is speaking of the bodily resurrection. Not the state of the spirit after death. You need to read I Thes 4:13-17. Particularly vs 14.
Rev 20:5 But the rest of the dead did not live again until the thousand years were finished. This is the first resurrection. Rev 20:6 Blessed and holy is he who has part in the first resurrection. The second death has no authority over these, but they will be priests of God and of Christ, and will reign with Him a thousand years.
Rev 20:12 And I saw the dead, the small and the great, stand before God. And books were opened, and another book was opened, which is the Book of Life. And the dead were judged out of those things which were written in the books, according to their works. Rev 20:13 And the sea gave up the dead in it. And death and hell delivered up the dead in them. And each one of them was judged according to their works. Rev 20:14 And death and hell were cast into the Lake of Fire. This is the second death.
Jesus hasn't come back yet - there is still sin in the world.