Are all sins forgivable?

Reading John 20:23 it says the Priest can retain a sin. Yet Catholics say “No sin is unforgivable.” Which is it?

These links should explain the Catholic Church’s teaching on unforgivable sin. If you have any further questions or concerns that are not answered by this, please contact Catholic Answers directly.**
Recommended Reading:
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[LIST]
]Is there a damnable sin?
]
Is there a sin that God won’t forgive?**
]* Is there a sin that will not be forgiven even with repentance?**
]* Does Hebrews 10:26-27 speak of another unforgivable sin?**
]* What is “blasphemy against the Holy Spirit” and why is it unforgivable?**
[/LIST]

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