Sahih Muslim, Book 8, Number 3421:
It had been revealed in the Qur'an that ten clear sucklings make the marriage unlawful, then it was abrogated (and substituted) by five sucklings and Allah's Apostle (peace_be_upon_him) died and it was before that time (found) in the Qur'an (and recited by the Muslims).
This verse is not found in the Qur'an today.
Why? Where is it gone?
More about the verse of suckling.
Abrogation is a rather problematic issue in itself.
The text of the Qur'an
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