Dear Alex:

Purgatory is not about paying the penalty of sin. Jesus on the Cross pays the penalty of our sin -- which is death. Those in purgatory are not in spiritual death; they are all headed to heaven.

Purgatory pays for the "consequences" of our sin, not for the sin itself.

For example, the standard analogy I use often is that if I throw a rock through your window I have committed a sin. I can become sorry for my sin and go to Confession and be absolved of that sin. Jesus paid the price for my sin.

But.....

.... the window is STILL broken. The broken window is the "consequence" of my sin and it still needs to be repaired. The Cross does not repair the window, that is my responsibility.

Thus, one of the aspects of purgatory is to pay for all the broken windows in our life that we did not get around to paying for during our life on earth.

As to why Purgatory? The answer is love. We cannot enter heaven unless we are perfected and totally holy. While we may die in a state of grace most of us are probably not perfect. Purgatory is a place of perfection. It purges the imperfections from us 'til what is left is pure gold.

1 Corinthians 3:12-15 is a great definition of Purgatory:

12 Now if any one builds on the foundation with gold, silver, precious stones, wood, hay, straw-- 13  each man's work will become manifest; for the Day will disclose it, because it will be revealed with fire, and the fire will test what sort of work each one has done. 14 If the work which any man has built on the foundation survives, he will receive a reward. 15  If any man's work is burned up, he will suffer loss, though he himself will be saved, but only as through fire.

In otherwords, how well we lived our lives as Christians will be judged, the good works and not-so-good works will be judge. The not-so-good works are the wood, hay, and straw that will burn up in the purging. The good works are the gold, silver, and precious stone that will survive the purging.

We cannot enter heaven with works that can be consumed. We must enter heaven only with works to our credit that can survive the fire. Thus God, who loves us so, provides a way for us to rid ourselves of the wood, hay, and straw in our lives so that we can enter heaven perfect and holy.

Again, this is NOT about purging sin, it is about purging the consequences of sin (paying for the broken windows) and about purging our imperfections in living the Christ-life.

Some Protestants call this the "Judgment Seat of Christ". Our salvation is not being judged here, rather how well we lived our life for Christ is being judged. While some Evangelicals refer to this as Judgment Seat of Christ and Catholics call it Purgatory, it is the same thing.

God Bless,
Bro. Ignatius Mary