Sahih Bukhari Volume 3, Book 39, Hadith 2291

وَقَالَ أَبُو الزِّنَادِ عَنْ مُحَمَّدِ بْنِ حَمْزَةَ بْنِ عَمْرٍو الأَسْلَمِيِّ، عَنْ أَبِيهِ، أَنَّ عُمَرَ ـ رضى الله عنه ـ بَعَثَهُ مُصَدِّقًا، فَوَقَعَ رَجُلٌ عَلَى جَارِيَةِ امْرَأَتِهِ، فَأَخَذَ حَمْزَةُ مِنَ الرَّجُلِ كَفِيلاً حَتَّى قَدِمَ عَلَى عُمَرَ، وَكَانَ عُمَرُ قَدْ جَلَدَهُ مِائَةَ جَلْدَةٍ، فَصَدَّقَهُمْ، وَعَذَرَهُ بِالْجَهَالَةِ‏.‏ وَقَالَ جَرِيرٌ وَالأَشْعَثُ لِعَبْدِ اللَّهِ بْنِ مَسْعُودٍ فِي الْمُرْتَدِّينَ اسْتَتِبْهُمْ، وَكَفِّلْهُمْ‏.‏ فَتَابُوا وَكَفَلَهُمْ عَشَائِرُهُمْ‏.‏ وَقَالَ حَمَّادٌ إِذَا تَكَفَّلَ بِنَفْسٍ فَمَاتَ فَلاَ شَىْءَ عَلَيْهِ‏.‏ وَقَالَ الْحَكَمُ يَضْمَنُ‏.‏

Narrated by Muhammad bin Amr Al-Aslami that his father Hamza said:'Umar R.A. sent him (i.e.Hamza) as a sadaqah collector.A man had committed illegal sexual intercourse with the slave-girl of his wife.Hamza took(personal)surities for the adulterer till they came to Umar.Umar had lashed the adulterer one hundered lashes.Umar confirmed their claim(that the adulterer had already been punished)and excused him because of being ignorent.