Some Christian traditions teach that Christians who die in good fellowship with the church but still not in a state of perfection will go to an intermediate place after death that is neither heaven nor hell. This intermediate place is known as purgatory. Unbaptized adults and those who have committed mortal sins, according to this tradition, go to Hades or hell. A few perfected persons (saints) go directly to heaven.
Defenders of purgatory teach that it will be a time and place of suffering, something akin to the lake of fire, but not as severe and only temporary. The amount of time one spends there depends on the degree of purging needed, based on one's sins. Pope Gregory I taught that baptism absolves us of original sin but that we have to remit payment for our actual sins. This purging is a preparation of the soul for heaven.
Is there any biblical justification for the doctrine of purgatory? Supporters of the doctrine generally defend their position by citing 2 Maccabbees 12:39-45 (a passage in the Apocrypha, or collection of writings that Protestants do not accept as a part of the Bible). But this text says nothing about purgatory, and those who do not accept the authority of the Apocryphal writings would not find it compelling even if it did. The other text that is sometimes cited is 1 Co 3:10-15, where the concluding phrase is "yet it will be like an escape through fire." But again there is nothing in the text that indicates that there will be a time and place after death in which individuals will be purged of the sins committed in this life.
The doctrine of purgatory fails the biblical test both in terms of direct interpretation of the specifically cited text and in terms of the overall teaching of Scripture. Neither of the classically cited passages mentions purgatory by name or by concept.
Even more, this doctrine denies one of the fundamental teachings of the NT-that Jesus' death on the cross atoned for all our sin, not simply original sin (Rm 3:21-26; 5:21). Because of that atonement, though we will all stand before the judgment seat of Christ, those who have placed faith in Christ will never face condemnation (Rm 5:1;8:1; 2Co 5:10).
Extracted from the Apologetics Study Bible.