حَدَّثَنِي مَالِكٌ، عَنْ زَيْدِ بْنِ أَسْلَمَ، أَنَّ رَجُلاً، اعْتَرَفَ عَلَى نَفْسِهِ بِالزِّنَا عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم فَدَعَا لَهُ رَسُولُ اللَّهِ صلى الله عليه وسلم بِسَوْطٍ فَأُتِيَ بِسَوْطٍ مَكْسُورٍ فَقَالَ ‏"‏ فَوْقَ هَذَا ‏"‏ ‏.‏ فَأُتِيَ بِسَوْطٍ جَدِيدٍ لَمْ تُقْطَعْ ثَمَرَتُهُ فَقَالَ ‏"‏ دُونَ هَذَا ‏"‏ ‏.‏ فَأُتِيَ بِسَوْطٍ قَدْ رُكِبَ بِهِ وَلاَنَ فَأَمَرَ بِهِ رَسُولُ اللَّهِ صلى الله عليه وسلم فَجُلِدَ ثُمَّ قَالَ ‏"‏ أَيُّهَا النَّاسُ قَدْ آنَ لَكُمْ أَنْ تَنْتَهُوا عَنْ حُدُودِ اللَّهِ مَنْ أَصَابَ مِنْ هَذِهِ الْقَاذُورَاتِ شَيْئًا فَلْيَسْتَتِرْ بِسِتْرِ اللَّهِ فَإِنَّهُ مَنْ يُبْدِي لَنَا صَفْحَتَهُ نُقِمْ عَلَيْهِ كِتَابَ اللَّهِ ‏"‏ ‏.‏

Malik related to me from Zayd ibn Aslam that a man confessed tofornication in the time of the Messenger of Allah, may Allah bless himand grant him peace. The Messenger of Allah, may Allah bless him andgrant him peace, called for a whip, and he was brought a broken whip.He said, "Above this," and he was brought a new whip whose knots hadnot been cut yet. He said, "Below this," and he was brought a whipwhich had been used and made flexible. The Messenger of Allah, mayAllah bless him and grant him peace, gave the order and he wasflogged. Then he said, "People! The time has come for you to observethe limits of Allah. Whoever has had any of these ugly things befallhim should cover them up with the veil of Allah. Whoever reveals to ushis wrong action, we perform what is in the Book of Allah againsthim." Translation Not Available

Book Ref: Muwatta Imam Malik Book 41 Hadith 1514
Web Ref:  Muwatta Imam Malik Book 41 Hadith 12