Summary: Everybody talkin' 'bout Heaven ain't goin' there. The Word of God is quite clear that many will be excluded from Heaven. The message is a plea to those who are casual about God to avoid this condemnation.
“[Christ, seated on His throne] said to [John], ‘It is done! I am the Alpha and the Omega, the beginning and the end. To the thirsty I will give from the spring of the water of life without payment. The one who conquers will have this heritage, and I will be his God and he will be my son. But as for the cowardly, the faithless, the detestable, as for murderers, the sexually immoral, sorcerers, idolaters, and all liars, their portion will be in the lake that burns with fire and sulfur, which is the second death.’” 
No more tears, no more death, no more mourning, no more crying, no more pain—this is the divine promise delivered in the first four verses of this chapter. I cannot imagine a time unmarred by tears, by death, by pain; tears, death and pain stain the path of mankind to this day.
John the Revelator has written, “I saw a new heaven and a new earth, for the first heaven and the first earth had passed away, and the sea was no more. And I saw the holy city, new Jerusalem, coming down out of heaven from God, prepared as a bride adorned for her husband. And I heard a loud voice from the throne saying, ‘Behold, the dwelling place of God is with man. He will dwell with them, and they will be his people, and God himself will be with them as their God. He will wipe away every tear from their eyes, and death shall be no more, neither shall there be mourning, nor crying, nor pain anymore, for the former things have passed away’” [REVELATION 21:1-4].
It is my practise to read these words when interring the bodies of those who served the Master. I read these words because they prove greatly comforting, providing, as they do, the promise of a new heaven and a new earth, the promise that God Himself shall wipe every tear from our eyes, the promise of the abolition of death and mourning and crying and pain! Throughout the long ages since John penned those words, the people of God have often found encouragement in these words that are yet to be fulfilled.
Easily missed, however, and immediately following these comforting words for saints, is a warning for those who have deceived themselves. With His warnings, our gracious God always provides an invitation, as all who name His Name should likewise do. “To the thirsty I will give from the spring of the water of life without payment. The one who conquers will have this heritage, and I will be his God and he will be my son” [REVELATION 21:6b]. Even as the message is delivered, the invitation of God is extended to all who will hear—an invitation to life, an invitation to receive the adoption of a child of God, an invitation to enter into the inheritance of the just. But then comes the warning, listing those who are excluded from these precious and eternal promises.
Even the most cynical of people would agree that this is a dark list representing the gross sins of this unbelieving world, with perhaps one surprising category of mortals. How can the fearful, the timid, the cowardly, be listed among those who are excluded from the Holy City? Explore the situation with me, discovering God’s view of sinful man that we might more effectively warn all to seek His grace and that we might ourselves seek to be delivered from that which dishonours God and insults grace.
THE DARK SINS — A survey conducted some years past revealed that over eighty-five percent of Americans assume they will go to Heaven at death. I would imagine that similar numbers hold true for Canadians. Everyone goes to Heaven, in the popular mythology. No doubt the most of those who responded to the survey are seriously self-deceived if we allow the Son of God to inform us concerning the issue of who goes to Heaven. The most of our fellow citizens anticipating Heaven see it as a reward, something earned through their own good deeds. You have perhaps heard someone say, “My good deeds will outweigh my bad deeds and that will be enough to satisfy God.” Scripture has a less sanguine view of mankind’s position before God, however.
Recall Jesus’ stern warning, “Enter by the narrow gate. For the gate is wide and the way is easy that leads to destruction, and those who enter by it are many. For the gate is narrow and the way is hard that leads to life, and those who find it are few” [MATTHEW 7:13-14]. This doesn’t sound like everyone goes to Heaven. The Saviour is cautioning that we deceive ourselves if we think otherwise.
Tragically, that narrow gate and the hard way are not attractive, and people imagine they can find an easier route to the celestial city. They fulfil the warning of the Wise Man: