Why does Catholic Church believe in purgatory?

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Tags

1. #purgatory
2. #necessary
3. #purification
4. #which
5. #still
6. #purified
7. #imperfectly
8. #enter
9. #church
10. #grace
11. #catholic
12. #undergo
13. #achieve
14. #holds
15. #friendship
16. #calls
17. #process
18. #heaven
19. #holiness