sometimes I can be a little dense. sorry about that. but are you saying that unless a person(Christian?) attains to sinless perfection while living, God will not accept him? Or are you talking about some purgatory-like experience, post physical death? I dont think you are, but nor do I believe that anybody attains sinless perfection in this life. If I am correct, and you are correct (that God only accepts sinless perfection) then it seems indeed heaven will be empty.
You are not at all dense. You have asked excellent questions.
No, I am not saying that one must "attain sinless perfection while living" in order that God accept him. Yet, God
will require such a state for those who will live forever with Him.
I will state a number of beliefs I have gained from the scriptures. Since previously I have quoted the references, I will simply state them now. If you need any reference just say so.
1. It is impossible to even become a disciple of Christ, without forsaking the self-life completely and following Him.
2. Through faith, together with the enabling grace made available by Christ's supreme sacrifice, it becomes possible to overcome sin and to live righteously.
3. "If anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new." So how could one who is in Christ still be living in sin?
4. God, who has begun the good work of regeneration, will continue
work in Christ's disciples for the purpose of their perfection, until the day Jesus returns. Then at our resurrection, the finishing touches will be put upon us, and we will be perfected as God intended. If this inner process is not presently taking place in a person's life, then it is questionable whether or not he is a disciple.
5. Within the hearts and minds (or souls and spirits) of Chist's disciples, God is working everything for good. He has preappointed then to be conformed to the image of Christ. He has called them; he has justified them; he has glorified them. This may also be a process, but spoken of in the past because God will surely do them. This process does not occur in a non-disiciple.
6. God works in a different way with non-disciples. He sends disciples to them to influence them or even lead them to take that first step in repenting and forsaking all to follow Christ. If they take that first step, then He works within them as described above. For they are then disciples.
I am not sure whether or not there are true disciples who do not coöperate with God's grace in working within them who make no progress at all in overcoming sin, or how God will deal with those who die immediately after becoming disciples. It seems that there are people whose names are written in the Lamb's Book of Life who will not share in the first resurrection (at Christ's return) but will find themselves raised with the wicked at the second resurrection (after the 1000 year reign of Christ) who will not be cast into the Lake of Fire with the wicked. I do not know how God will deal with them as I do not find any information on that in the Scriptures.