Obviously, the purpose of the Spirit is the working out of the plan of God. Therefore, we know that his goal as far as his people is concerned is that they would be delivered from the presence of their sins. It is possible that some of them will be converted a few minutes before Jesus returns. If that is the case, then the Spirit will regenerate them in the same way as he has regenerated all those before them, by giving to them spiritual life.
They will join the believers still alive and who are in the process of being sanctified. The Spirit will work in them to purify them, to purge them of their sins. Even although there will not be long until Jesus returns, the path of sanctification will continue for them as they make progress in holiness. Yet we know that as long as they are sinful, the goal of the Spirit has not been reached.
In contrast to those believers still living on earth, there will be all the believers who have died and gone to heaven. As far as their souls are concerned, they are perfect in holiness. Yet even they have not reached the goal, because their bodies have yet to be resurrected. So, while sinless in heaven, they anticipate what will occur when the goal of the Spirit will have been reached.
So what is the goal of the Spirit, we might ask. The goal is for all of his people to be conformed to the image of Jesus. In other words, they will be glorified; those who had died in Jesus will be resurrected with an incorruptible, immortal body, now reunited with their souls; those who were living when Jesus returns will be changed, in a moment they will be sinless and they will have the fruit of the Spirit in balance and fullness.
Words cannot describe what this event will be like, but we are assured in the Bible that it is the goal of the Spirit to bring all his people into the full experience of eternal life, to the glory of God