"Purgatory exists because of the mercy of God. If there were no purgatory, this would also likely mean no salvation for most people. God is merciful indeed."
Purgatory is not about a sadistic God who wants to see us suffer under His gratuitous torture. It's also not a second chance to get into Heaven. It's only for those who have died in the friendship of God, yet having lingering attachments to sin. If you find yourself in Purgatory, Thank God! You'll be in Heaven when your impurities are finally and fully purged from your soul. This is the final APPLICATION of the cleansing blood of Jesus.
Not every Christian will need purgatory. Those newly baptized are pure (though if the they live very long after that they'll begin to sin). Martyrs are purified through their mode of death. And for Catholics, if you've made a good confession with perfect contrition and penance you are pure as newly baptized. Friends of Jesus who don't believe in the Sacrament of Penance will be purged of their imperfections in Purgatory, excepting the newly baptized.
Our word "hell" is used for two words in Hebrew: Gehenna and Sheol. Gehenna is Hell of eternal damnation and Sheol is a 3rd place of being, aka "Abraham's Bosom" and possibly "Paradise". Sheol is sometimes translated to "Hades".
OT references to a 3rd state of being which is neither Heaven nor Hell-Gehenna:
Gen. 50:10; Num. 20:29; Deut. 34:8 - ritual prayer and penance for the dead
Zech. 9:11 - A prophecy of Jesus descending to Hell-Sheol to free the "spirits in prison".
2 Macc. 12:43-46- "holy and wholesome thought to pray for the dead". This implies a place which is neither Hell-Gehenna nor Heaven. That place is Hell-Sheol.
Under the New Covenant Sheol is no longer exists, but a new "place" does... we call it Purgatory. The root word of "purgatory" is in Scripture (KJV)...
John 15
I AM the true vine, and my Father is the husbandman.
2 Every branch in me that beareth not fruit he taketh away: and every branch that beareth fruit, he purgeth it, that it may bring forth more fruit.
A "branch that beareth fruit" is a child of God. God purges impurities in a person in order to make them more fruitful (more holy). This can happen in this life and it can happen after death as the final and complete purging. Believers reach maximum/perfect "fruitfulness" at some point before entering God's presence, since nothing impure can be in His presence. Most of us don't attain perfect holiness in this life, so in His Mercy He finishes our sanctification after death and before entering His presence.
Matt5:25-26: A parabolic statement that if we are not purified before death we will be so after death before entering heaven. Similarly, Matt18:34,Luke12:58-59. "Prison" cannot be Hell-Gehenna, because once there, there is no getting out, no parole. However, in Hell-Sheol, the righteous dead awaited release which happened after Christ went there after His death.
If we die in the friendship of Christ yet with any lingering spiritual imperfections, we'll be "in prison" until the "debt" is paid. The merits earned by Christ are then finally & fully applied, purging us of impurity. This is the 3rd place. It's called Purgatory, it's the New Covenant version of Sheol of the Old Covenant.
Matt. 12:32 "in this world or in the next". This implies a 3rd place since in heaven forgiveness is unnecessary and in Hell-Gehenna forgiveness is not possible.
Luke 16:19-31: The rich man (whose only sin was not helping a beggar) is not in Hell-Gehenna (and certainly not heaven) but a 3rd place, Hell-Sheol. Lazarus is likewise in Sheol. BC, all the dead (good and bad) went to Sheol to await Christ. Apparently there were different levels of Sheol. In this parable, Lazarus, who was a good man but afflicted in life, was in a better place within Sheol.
1Cor15:29-30
"baptized for the dead" a form of prayer for the dead. Implies that after dying we don't necessarily immediately go to heaven, but something or someplace is in between, on the way there.
Philip2:10
"under the earth" suggests a 3rd place. This can't be hell-Gehenna because in hell there is no grace to empower people to give Jesus worship.
2Tim1:16-18
Paul prays for Onesiphorus. This implies a 3rd place since in heaven mercy is unnecessary and in Hell-Gehenna there is no mercy.
Heb. 12:23
"spirits of just men made perfect". No one is just (justified) without having accepted Jesus as their Lord, but the just are not necessarily perfect enough to see God's Face (although those such as newly baptized or martyrs are perfected). We inevitably sin (minor though they may be) after accepting the Gift, and if we die without having repented of such sins we are not pure, but will be purified before getting into heaven.
1 Peter 3:19; 4:6
After His death, Jesus preached to "spirits in prison" & "them that are dead" This implies a 3rd place neither Heaven nor Hell-Gehenna because in heaven they don't need preaching to and in Hell they can't benefit from preaching.
Rev. 21:27
"And there shall in no wise enter into it any thing that defileth". Being born again means the primary effect of Original Sin (loss of God's grace) is erased. We receive the grace and become God's child. Yet we still tend to sin. These personal sins are also forgiven, but not in a blanket pardon at the beginning of our new life in Christ. They are forgiven on a case by case basis as we commit and repent of them. Many Christians will die with some unrepented sins or lingering attachments to sin. Before they can get into Heaven, those impurities are washed, or burned, away in a place which is neither heaven nor hell: purgatory.
The concept of Purgatory is tied to the concept of Justification and Original Sin. Protestants & Catholics have slight, yet significant, differences on what these are and what their effects are. Here is a comparison on Justification: http://vivacatholic.wordpress.com/223-2/ .
The concept of Justification is based in the understanding of Adam&Eve's first rebellion, which Catholics call Original Sin. Before that Sin, mankind was pure & holy, part of God's family, they were indwelt with the Holy Spirit, they were "justified". Had they not sinned, their children would also have had the Spirit, and been holy children of God. The primary effect of Adam's sin was loss of divine sonship, loss of the Spirit, loss of "justification". Since they did not have the Spirit, their offspring could not inherit it, so all subsequent humanity would be born in an unjustified state. (That's the reason our own spiritual life was effected by that long-ages-past ancestor.) Other effects are weakened will (can't resist sin on our own), disordered desires (we often crave that which is harmful), and darkened intellect (we're stupider than if Adam hadn't sinned). Because of those effects, we tend to sin (that's called concupiscence). Another side-effect is limited physical lifespan.
When we are "justified" we are born into the family of God, adopted as His children, purified, made holy, "infused" with righteousness, indwelt with His Spirit. This undoes the primary effect of Original Sin. But, the side-effects remain and we deal with those throughout our earthly life and grace helps us in that.
The Protestant concept of Justification is that God "imputes" His righteousness upon us, not actually making us pure & holy, just concealing our ugly impurity with His purity.
If you accept the Protestant understanding of Justification, you would logically have to reject the concept of Purgatory. But the Catholic understanding of Justification leads naturally to the concept of Purgatory. So, I look to documentary history to see how Christians of the Apostolic age, and immediately thereafter, understood Justification. http://www.staycatholic.com/ecf_justification.htm lists quotes of early Christian writers. Catholic teaching is in accord with these early Christians, that we are justified by more than faith alone.
Here are some Ancient writings featuring belief in the 3rd Place... they didin't use the word "purgatory" but the concept is present in writings as far back as 2nd century. The doctrine could not likely be a novel innovation at that time because there are no ancient writings debating the issue. (Unless I just haven't seen them.) http://www.cin.org/users/jgallegos/purg.htm
Purgatory, Holy Fire: http://zuserver2.star.ucl.ac.uk/~vgg/rc/aplgtc/hahn/m4/pg.html
John Salza's Site: http://www.scripturecatholic.com/purgatory.html
