Sahih Bukhari, Volume 8, Book 82, Number 816:
'Umar said, "I am afraid that after a long time has passed, people may say, "We do not find the Verses of the Rajam (stoning to death) in the Holy Book," and consequently they may go astray by leaving an obligation that Allah has revealed. Lo! I confirm that the penalty of Rajam be inflicted on him who commits illegal sexual intercourse, if he is already married and the crime is proved by witnesses or pregnancy or confession." Sufyan added, "I have memorized this narration in this way." 'Umar added, "Surely Allah's Apostle carried out the penalty of Rajam, and so did we after him." (See also: Vol. 8, No. 817 and Vol. 9, No. 424; Sahih Muslim, No. 4194)
Why is the verse on stoning for adultery not found in the Qur'an?
A more detailed discussion of this topic can be found in John Gilchrist's Jam' al-Qur'an, Sam Shamoun's article, Islam and Stoning: A Case Study Into the Textual Corruption Of the Quran, and in this summary of hadiths and quotations from early Muslim scholars taken from John Burton's "The Collection of the Qur'an".
The Text of the Qur'an
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