Because your righteousness is already complete.
Therefore if any man be in Christ{present perfect tense], he is [present tense] a new creature: old things are passed away [past tense]; behold, all things are become new [present perfect tense]. And all things are of God, who hath reconciled us [past tense] to himself by Jesus Christ, and hath given to us [past tense] the ministry of reconciliation; (2 Corinthians 5:17-18 KJV)
So if you are in Christ, you are reconciled unto him. Now! Not later. Now. There is no future punishment for your sins. No matter how wretched you see yourself, you have been reconciled unto him. You are not defiled because Christ has made you righteous through faith.
It always amazes me how the Roman Catholic Church seems to ignore wholesale the teaching of the Book of Romans. But one cannot really read the Book of Romans and not walk away knowing that if you have faith in Christ that the only thing awaiting you after death is Life. Abundant life. No more suffering and no more tears.
Those who teach Purgatory teach another gospel. Sorry, but it is ANOTHER Gospel.
1. there is nothing biblical in saying because you think you're saved you are.
2. I don't see anything necessarily stopping God from revoking salvation on his own Judgement.
"Mat 7:23 And then will I profess unto them, I never knew you: depart from me, ye that work iniquity."
"Those who teach Purgatory teach another gospel. Sorry, but it is ANOTHER Gospel."
True. It's not the "gospel" (as interpreted by some) according to Paul in Romans.
It's the Gospel according to Jesus, in the Gospels.
Where he says "Gehenna", and where he tells people what they have to DO (ongoing basis) to not get thrown there.
I can't see any basis to read Paul to overrule Jesus.
So I don't do so.
It seems to me that Jesus laid out a simple and clear set of beliefs and standards, and called for the repentance for those who fall short. He set a standard of judgment which differs for each man (i.e., a subjective standard, based on the man, not an objective standard based on fixed punishments) in which he says you will be judged using the standard you have used to judge others. An example where Jesus saved people from doing something heinous? "Let he among you who is without sin cast the first stone."
The further we track away from Jesus' words and deeds, the more of a morass the Bible becomes.