Introduction - Preliminary thoughts
At first thought there doesn't seem to be a need to preach the gospel in heaven (for the purpose of salvation or of edification for believers). In the new heavens and new earth, there will be no sin, nor suffering, nor pain (Rev 21:1-4), so gospel preaching of warning, repentence and comfort would be obsolete in that sense. So if we will be glorified in the ultimate sense and given new resurrection bodies, what place would the gospel have for all eternity?
Furthermore, if the word of God is the gospel, and in the beginning there was the word, and the word was with God and the word was God (John 1:1), perhaps the parousia (the revealing) of Jesus will render that "obsolete". Not that God's word (i.e. The Word of God incarnate) is ever obsolete, but if we are to be in the very presence of God, where the city of heaven will be God's tabernacle (temple), then God will herald himself.
On the idea of bringing glory to God, if we see that salvation is from God, for God's glory, then the end is God's pleasure and glory, while the means is God himself through the gospel (revelation of Jesus). So since God's glory will be fully consumated and we will share in that by his grace, there will also be no need to herald the gospel for God's glory, because we will be praising God directly before his throne.
Theological themesSince there are many theological themes and functions we could bring into this, let's focus on a few of them for now.
1. A brief survey of the heraldic gospel:
The gospel was preached in the Old Testament in a way that was anticipatory, the full blessings of God's gospel hadn't yet come during the time of the prophets, priests and Kings. So when the preaching of the Kingdom finally came with John the Baptist, the message was of repentance for the Kingdom was at hand. Jesus is the culmination of those great promises as he was the one the prophets pointed towards and where the gospel finds its centre, with his death, resurrection and ascension meaning victory of death and the power of sin, now is the age where the gospel is preached to the world. When Jesus comes again, the preaching of the Kingdom won't be in the same way as before, but I think the continual praise and glory will still be focussed on God climatically.
2. The City of God
The city of God theme is significant, as the city is described in the same terms as the Holy of Holies (Rev 21:16). This means that there is ultimate intimacy between God and the elect, and in that sense there will be no more heralding of the gospel (if we assume that the function of heralding the gospel is to mediate God to people or to bring people to repentance). But the heralding can take a different form can't it? It could be a praising adoration for all eternity, which is in fact what eternity will be! There's no reason for us to think it can't be an eternity where we learn for all time God's immeasurable grace and power.
But the eternal plea will always be that Jesus lived and died for us - that is the gospel. We can't praise God for all eternity without constantly remembering the grounds by which we are there in the first place; and that brings us to the gospel again and again. So we herald it in that sense, not in a way to bring people into the Kingdom, but to recognise in our praise that we are with God on the basis of what Christ has done for us at the Cross. The image of the slain lamb and the lion being praised (Rev 5:5-6), and other images of Jesus bring praised by the multitudes perhaps bring this into sharper focus.
3. Kerygma and Doxology
It's also important to note that in the new heavens and the new earth, kerygma and doxology will be intertwined. What stands between the two now is sin and anticipation till the end. Most Christians tend to think that biblical lines of continuity stops at the Cross; but there's biblical theology exercised in the New Testament isn't there - both backwards and forwards. Backwards in the sense the the gospel has secured salvation and nothing saves us apart from the grace of God shown at the Cross. And forward in the sense that we are awaiting the adoption of Sons, Romans 8, and you can't read Romans 8 without reading Romans 1,2 and so on.
Further reflection on the Resurrection
It's important also to recognise that while we are given Resurrection bodies (Phil 4, 1 Cor 15), we are not given divine bodies as our being; that is, we are not absorbed or transformed into some divine being other than human. The human is glorified as the perfect resurrected human and is transformed in that sense. We are
not given deity in that we become absorbed into the Godhead (which some Christians believe, based on a misinterpretation of 2 Peter 1). What this means is that there's no way we'll then come into an omniscient knowledge of God. The incommunicable attributes of God (like all the "omni" attributes) will be incommunicable still in the new heavens and the new earth. We will know and see God perfectly as perfect human beings, but human beings we still remain. Just as how Christ is still the God-man today, or else he couldn't be that high priest that Hebrews 2 describes. One mistake I made in my systematic theology in the past was that I argued that Jesus released some attributes of God when he took on human attributes (the position called the 'kenosis' of Jesus, his emptying), that was just plain fundamentally wrong. Jesus on top of his perfect divine being, took on humanity.
ConclusionWhat this means for us is that we will be resurrected with the same kind of resurrection body Jesus had in all its glory, never to be corrupted by death again, but our knowledge of God will only be on the outskirts (even as it is now) as we know Him truly for who He is. In other words, we have an eternity to know an infinite God. And the way we'll get to know this God is not in the functional worldly sense of preaching today with a preacher behind a pulpit, but in the functional heavenly sense of preaching in that God will reveal himself utterly, completely to us insofar as we resurrected people will be able to understand and for all eternity, without it being esoteric, and in unshielded presence and intimacy for ever and ever. It is then that the barrier of sin in our current lives will be no more. We will at last, be completely conformed to the living God, in whose image we have been made (2 Cor 3:18).
Praise be to the God and Father of our Lord Jesus Christ! In his great mercy he has given us new birth into a living hope through the resurrection of Jesus Christ from the dead, and into an inheritance that can never perish, spoil or fadeākept in heaven for you, who through faith are shielded by God's power until the coming of the salvation that is ready to be revealed in the last time.
- 1 Peter 1:3-5