Sunan an-Nasa'i 4811
It was narrated from Ibn 'Abbas tht the Prophet said:
"The Mukatab is free to the extent that the has paid off (toward buying his freedom); he Hadd punishment should be carried out on him proportionate to the amount he has paid off (toward buying his freedom); and he inherits proportionate to the amount he has paid off (toward buying his freedom)."
أَخْبَرَنَا مُحَمَّدُ بْنُ عِيسَى بْنِ النَّقَّاشِ، قَالَ حَدَّثَنَا يَزِيدُ، - يَعْنِي ابْنَ هَارُونَ - قَالَ أَنْبَأَنَا حَمَّادٌ، عَنْ قَتَادَةَ، عَنْ خِلاَسٍ، عَنْ عَلِيٍّ، وَعَنْ أَيُّوبَ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏
"‏ الْمُكَاتَبُ يَعْتِقُ بِقَدْرِ مَا أَدَّى وَيُقَامُ عَلَيْهِ الْحَدُّ بِقَدْرِ مَا عَتَقَ مِنْهُ وَيَرِثُ بِقَدْرِ مَا عَتَقَ مِنْهُ ‏"‏ ‏.‏