v. 11 Pretty self explanatiory. JESUS is the only foundation.
v.12-13 If a man is saved, he then builds on the foundation of Christ with his works, not to get saved or stay saved because the foundation is there always. These works will be manifest, (made such as a physical substance) as gold, silver, etc.
v.14-15 Any works, works not souls, that withstands the test of fire will be rewarded. The works that do not survive the trying by fire, such as hay wood or stubble would not survive, will suffer a lose of a reward that they could have received if the work had been done pure.v.15 clearly indicates that the writer is speaking of works performed by each person, not the person himself.
Heb.10:12 But this man, after he had offered one sacrifice for sins forever, sat down n the right hand of God.
Heb.10:14 For by one offering he hat PERFECTED FOREVER them that are sanctified.
Perfected forever. You say you have to go to purgatory to be perfected, God says Jesus' did it for us forever.
Becky
Your gloss on 1 Corinthians3:15 is mistaken. It refers to the person not the works.
Let's just do a common sense analogy. Let's say a man, not a Christian, robs a bank. He has to go to jail for 20 years. After he has served one year of his sentence, he repents and becomes a Christian. It is a genuine conversion. Does he get to go to the judge and say, "Okay your Honor, I have accepted Christ, and he paid the price for my sin of bank robbery. Therefore you have to let me out of jail. I don't have to serve the remaining 19 years of my sentence. Christ has perfected me." Of course not! The man still has to pay an temporal (earthly) price for his sin. And a Christian he accepts this. Christ's death on the cross did not free us from having to pay a temporal price for our sins. What it did do was make it possible for us to attain heaven if we repent of them and accept him. Christ paid the eternal price but not the temporal price.
Another example. A guy is a drug addict. Because of this he he beat his wife, impoverished his children and robbed many people to feed his habit. Then he coverts and through the grace of God his sin is forgiven. But life does not just turn rosy for him. He has a lot of work to do to get back the love and trust of his family. He still has to pay a price, even though Christ has forgiven his sin. If he dies before he has fully paid that price, then he will pay it in purgatory, even though he is forgiven and knows heaven awaits him. Some of his purgatory will be on earth as he struggles with the effects of his sin and pain it has caused others and the hardship of putting his life back together.
It is common sense and biblical. And it is not only that but it is simple justice too. If a murderer goes unpunished during this life but converts to Christ on his death bed, by your logic he goes straight to heaven. Whereas a murderer who spent 40 years in prison and then converts on his death bed, by your logic also goes straight to heaven. But that is unjust because one was punished for 40 years and the other was never punished.