Sahih Bukhari Volume 8, Book 86, Hadith 6831

حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، عَنِ الزُّهْرِيِّ، عَنْ عُبَيْدِ اللَّهِ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ قَالَ قَالَ عُمَرُ لَقَدْ خَشِيتُ أَنْ يَطُولَ بِالنَّاسِ زَمَانٌ حَتَّى يَقُولَ قَائِلٌ لاَ نَجِدُ الرَّجْمَ فِي كِتَابِ اللَّهِ‏.‏ فَيَضِلُّوا بِتَرْكِ فَرِيضَةٍ أَنْزَلَهَا اللَّهُ، أَلاَ وَإِنَّ الرَّجْمَ حَقٌّ عَلَى مَنْ زَنَى، وَقَدْ أَحْصَنَ، إِذَا قَامَتِ الْبَيِّنَةُ، أَوْ كَانَ الْحَمْلُ أَوْ الاِعْتِرَافُ ـ قَالَ سُفْيَانُ كَذَا حَفِظْتُ ـ أَلاَ وَقَدْ رَجَمَ رَسُولُ اللَّهِ صلى الله عليه وسلم وَرَجَمْنَا بَعْدَهُ‏.‏

Narrated By Ibn 'Abbas : '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."