Not Phantoms

They represent the heavenly side of the coming glory, just as Peter, James, and John in natural bodies portrayed the earthly side of the kingdom.
Furthermore, Moses and Elijah were not angels, nor did they appear as angels, for "there talked with Him two men, which were Moses and Elias." Another point to discover here is that even those in natural bodies, such as Peter, James and John, needed no introduction to those in glorified bodies, although they had never seen them on earth.
Another scripture that deals with this subject and is irrefutable in combating the idea that we will not know one another in heaven is found in the second chapter of First Thessalonians: "For what is our hope, or joy, or crown of rejoicing? Are not even ye in the presence of our Lord Jesus Christ at His coming? For ye are our glory and joy." vv. 19, 20. Not only will the Apostle Paul know those Thessalonian believers in the glory and they know him, but they are to be manifestly his joy and crown of rejoicing. They will be there as the evident trophies of Paul's labors at Thessalonica.