Second Coming
The Second Coming (sometimes called the Second Advent or the Parousia) is a Christian and Islamic belief regarding the future (or past) return of Jesus Christ after his ascension to heaven about two thousand years ago. The idea is based on messianic prophecies and is part of most Christian eschatologies.
Premillennialism
Premillennialism, in Christian eschatology, is the belief that Jesus will physically return to the earth (the Second Coming) before the Millennium, a literal thousand-year golden age of peace. The doctrine is called "premillennialism" because it holds that Jesus' physical return to earth will occur prior to the inauguration of the Millennium. Premillennialism is based upon a literal interpretation of in the New Testament, which describes Jesus' reign in a period of a thousand years.