As always, thanks for your questions.
Purgatory exists only as a result of the Blood of Christ. The Scriptures tell us that we must be holy as God is (not in degrees, but in likeness!). We are told that unless OUR righteousness (not Christ's thrown over us like a coat) exceeds that of the Pharisees, we shall not see heaven (Mat 5:20). Considering the context of Matthew 5-7, Jesus is clear that He instructs US to Love from the heart. He is telling us to give alms, to pray, to fast - NOT just to do it externally for human pride, but to do it for the Love of God and neighbor. This is the righteousness that God desires from us (understand, WE don't do this alone - but with God's Spirit working within us the will to follow Him). Nowhere in Matthew 5-7 does Jesus talk about imputed justification or anything like it. It is clear that Jesus expects US to be holy, to be clean of heart, to be meek and humble, to be poor in spirit...
Most of us will not achieve that level of righteousness here on earth. We will likely have attachments to things of the world. Our pride. We will not place God first in everything. This must change before eternal union with God. Could you imagine God and Luther's idea of man co-existing forever? It is incomprehensible. God is not some foolish old dolt who doesn't recognize the smell of our stinking selves (spiritually) underneath the "cloak" of Christ... I never did understand that mental picture.
Since we all sin after salvation (or initial salvation) then does every ultimately saved person go to purgatory for a time? Or, does everyone who was "right" with God and had confessed all sins before death get to bypass purgatory?
Sins are not forgiven in Purgatory, but here on earth. We are punished for the temporal results of our sins in purgatory, first of all. An example might help. Let's say your son breaks a window. He apologizes. He is forgiven. But what about the window? Do we ignore the fact that the window is broken? As a parent, we have a right and a DUTY to serve some sort of corrective to our child. Some will make the child work or do extra chores. Spankings. Groundings. Take away the toy. In any case, the child must suffer some consequences for their action. Not only that, the child is punished for the sake of discipline and for developing virtue. God does that with us, as the Scripture tells us. He continues this in Purgatory.
Secondly, Purgatory is for purging away attachments and our vices that remain within our will and intellect after our death. Few of us will die with God as the treasure of our hearts, without pride, ego, or envy, for example. I imagine that our particular judgment, our opening of our eyes at the reality of God, we will PINE for God - it will be a suffering, one where we will let go of our wills that differ from God's.
Purgatory will be experienced by the majority of the saved.
Regards
I suppose then, that we would disagree on the meaning of the Sermon on the Mount. I would say the reason Jesus does not speak of imputed justification is that He was not talking about salvation in the Sermon. He was talking about righteous living, which we are to seek, and is as you said, possible through God inside us. Even in 5:20, this is a description of the new nature, not a "to do" list.
I actually like the idea of Christ's righteousness being thrown over me like a coat. In my sinful nature I am very cold. :) In order for me to cooperate in righteousness I must add at least an element of my own, do you agree? I would say there is no righteousness in me to add. None. I can't cooperate if I don't bring anything to the table. I see this whole "view" as being meek and humble, and poor in spirit. This is part of what attracts me to it.
Could you imagine God and Luther's idea of man co-existing forever? It is incomprehensible. God is not some foolish old dolt who doesn't recognize the smell of our stinking selves (spiritually) underneath the "cloak" of Christ... I never did understand that mental picture.
I'm not directly familiar with Luther's quote, but I think I get the drift. I believe God knows "who" we are in our sin, and He is not ashamed of what He made. We are just not fit to exist with Him in heaven for all time. (God created lots of things that will not exist with Him heaven.) Christ fixes this problem for us, we did not have the means. God knows our "smell", but does not count it against us because of what Christ did. It is as if God ignores our "smell". Do we not all sometimes ignore glaring faults in those we love? The cloak of Christ's blood trumps the smell and in God's eyes it is wiped away.
Of course, the other way to look at it is that we really don't "smell" so bad at all, since we have a new nature in righteousness. Yes, there are remnants that stink, but the core of our new being is holy. Christ's work caused this to happen. In either case, the result is the same. We are unworthy, Christ loved us and did what we could never do. Here we would disagree on the cooperation issue. I know you have said that cooperation is enabled by God, but the whole freewill idea means the decision comes from us. Is man glorified in his cooperation?
Thank you for your further comments on purgatory.
God bless.