When Paul summarizes the resurrection theme in the Corinthian letter, he is writing to some who were denying the resurrection, which may be the result of the perverse teachings of Hymenaeus and Philetus who taught it had already passed. If it had already passed, then the obvious conclusion is that some were not expecting it, anymore. This fact, along with the Sadducean view of no resurrection at all, shows that people were divided over this subject.
In Revelation 20:4-6, John sees the first resurrection within the same context with the marriage of the Lamb. He sees the Son of Man coming to take his bride which is commensurate with the thousand-year reign of Christ. This is paramount to the bridegroom presenting his bride or kingdom to the Father, as is taught in 1 Corinthians 15. Keep in mind that before he does this, he comes as a valiant warior to take vengeance on old Jerusalem (Rev. 19:11-16). The first resurrection is the harvest day or the cleaning of John’s “threshing floor” where the wheat is put into the barn while the chaff is burned. This was a first-century prediction and fulfillment that must be fulfilled in ending the old Jewish regime for the saints to reign with Christ.