When does the regeneration of the earth occur?
The regeneration of the earth occurs during the thousand-year period, when the earth is brought back and made like the Garden of Eden. At that time the Son of Man will sit on the throne of His glory. This is the same thousand-year period.
Les explains that Jesus was not speaking of salvation, which had been established when Peter said, 'Thou art the Christ.' Peter, like Abraham, sought assurance. Jesus answered that those who followed Him would be in the regeneration—when the earth is brought back and made like the Garden of Eden. Les identifies this regeneration as the same thousand-year period, when the Son of Man sits on the throne of His glory. He also notes that during Christ's earthly ministry, except for the Mount of Transfiguration, He did not reveal His glory.