Must prayers performed incorrectly for years be repeated?

Question

Some people had been praying for a long time, but they had learned the prayer incorrectly; now they have corrected it with the imam. The question is: must the incorrect prayers of the past ten, twenty or thirty years be made up (qada’) or not?

Answer

Not correcting one’s prayer from the very beginning is a very great shortcoming. Nevertheless, they performed the prayer regularly in the way they knew it; may Allah the Exalted forgive whatever shortcoming and error occurred. Now they will not be ordered to pray again the prayers of ten, twenty or thirty years.

Source: Fatawa Mahmudiyya

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