They are Firstfruits. first fruits of what?
Rev 14:4 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.
Rom_8:23 And not only they, but ourselves also, which have the firstfruits of the Spirit, even we ourselves groan within ourselves, waiting for the adoption, to wit, the redemption of our body.
The disciples had the first fruits of the Holy Spirit.
Jas_1:18 Of his own will begat he us with the word of truth, that we should be a kind of firstfruits of his creatures.
The new creature is a first fruit.
So the question is how are the 144,000 who have the seal of God firstfuits?
Well for one they are like God just like the disciples were when they received the Holy Spirit.
The answer is in the outpouring of the Spirit.
Act 2:16 But this is that which was spoken by the prophet Joel;
Act 2:17 And it shall come to pass in the last days, saith God, I will pour out of my Spirit upon all flesh: and your sons and your daughters shall prophesy, and your young men shall see visions, and your old men shall dream dreams:
Act 2:18 And on my servants and on my handmaidens I will pour out in those days of my Spirit; and they shall prophesy:
Act 2:33 Therefore being by the right hand of God exalted, and having received of the Father the promise of the Holy Ghost, he hath shed forth this, which ye now see and hear.
So Peter quotes Joel and the outpouring of the Holy Spirit which we have seen made them first fruits. But when we got to Joel we learn something interesting:
Joe 2:28 And it shall come to pass afterward, that I will pour out my spirit upon all flesh; and your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions:
Joe 2:29 And also upon the servants and upon the handmaids in those days will I pour out my spirit.
Notice what it says before this concerning this outpouring.
Joe 2:23 Be glad then, ye children of Zion, and rejoice in the LORD your God: for he hath given you the former rain moderately, and he will cause to come down for you the rain, the former rain, and the latter rain in the first month.
There is more than one Rain. the Former we saw at Pentecost. But the latter only comes when the harvest is about ready to be harvested fully. The Former started the growth of the seed. Thus the Christian church began with the former rain the outpouring of the Spirit.
The latter rain comes to ripen the harvest when the harvest is nearly ready.
Notice that when the disciples received the Holy spirit they gave a message of repentance and of Jesus and the church began to grow under the former rain of the Spirit.
Notice also that there is a message given by the 144,000 in Revelation 14.
Rev 14:6 And I saw another angel fly in the midst of heaven, having the everlasting gospel to preach unto them that dwell on the earth, and to every nation, and kindred, and tongue, and people,
Rev 14:7 Saying with a loud voice, Fear God, and give glory to him; for the hour of his judgment is come: and worship him that made heaven, and earth, and the sea, and the fountains of waters.
Rev 14:8 And there followed another angel, saying, Babylon is fallen, is fallen, that great city, because she made all nations drink of the wine of the wrath of her fornication.
Rev 14:9 And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead, or in his hand,
Rev 14:10 The same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb:
Rev 14:11 And the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name.
Rev 14:12 Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.
This message is followed by a harvest.
Rev 14:14 And I looked, and behold a white cloud, and upon the cloud one sat like unto the Son of man, having on his head a golden crown, and in his hand a sharp sickle.
Rev 14:15 And another angel came out of the temple, crying with a loud voice to him that sat on the cloud, Thrust in thy sickle, and reap: for the time is come for thee to reap; for the harvest of the earth is ripe.
The 144,000 will have to be sealed first then they will give a final message of repentance to the world under the power of the latter rain of the Spirit, then Christ will harvest the earth at his coming.