Several questions present themselves as we study this passage. Here is the passage in question:
Revelation 14:1 And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads. 2 And I heard a voice from heaven, as the voice of many waters, and as the voice of a great thunder: and I heard the voice of harpers harping with their harps: 3 And they sung as it were a new song before the throne, and before the four beasts, and the elders: and no man could learn that song but the hundred and forty and four thousand, which were redeemed from the earth. 4 These are they which were not defiled with women; for they are virgins. These are they which follow the Lamb whithersoever he goeth. These were redeemed from among men, being the firstfruits unto God and to the Lamb. 5 And in their mouth was found no guile: for they are without fault before the throne of God.
First, are these 144,000 the same as those found in Revelation 7:1-8? Obviously, they are. Another group would certainly be identified in a way that made the difference clear. They must be those sealed in chapter seven.
Second, where are they: on earth or in heaven? There is a mount Sion (or Zion) on earth, but God’s heaven is also called mount Sion (see Hebrews 12:22 – “But ye are come unto mount Sion, and unto the city of the living God, the heavenly Jerusalem, and to an innumerable company of angels”). This Sion is clearly the one in heaven. The 144,000 are redeemed “from the earth” (v.3) and they are “before the throne of God” (v.5). Everything points to them being in heaven in chapter 14.
Third, when are we seeing them with the Lamb in heaven? Is it during the time of the tribulation or is it after the end of the tribulation? Since the book of Revelation does not seem to be in perfect chronological order, this is difficult to say for sure. However, I believe that it probably occurs before the very end of the tribulation because they are seen with the Lamb (Jesus Christ) up in heaven. At the end of the tribulation, Jesus Christ will come down to earth. Therefore, this must be before that time. This passage also states that the 144,000 will “follow the Lamb whithersoever he goeth” (v.4). Evidently, they will return with Christ when He comes to earth as recorded in Revelation 19.
Fourth, is this a resurrection? It may be, but consider this: there cannot be a resurrection unless the 144,000 die and there is no record of them dying. Instead, we are told that they are sealed, “having the seal of the living God” (Revelation 7:2). Although this seal may be related to eternal security, as in the case of grace-age believers, I think it is most likely a seal of protection on them during their tribulation ministry. In Revelation 7:2-3, the four angels are kept from hurting the earth and the sea until the 144,000 are sealed. I believe this seal provided a form of protection while they performed the work of God in a very hostile environment. If this is true, then instead of a resurrection, Revelation 14:1-5 may indicate an ascension.
At least, at this point, that is my understanding of the passage. The 144,000 have completed their work on earth and have been taken up into heaven before Christ returns at the end of the tribulation on a white horse and with His saints. Evidently, the 144,000 will return with Him.