(6) باب قَوْلِ اللَّهِ تَعَالَى {أَوْ تَحْرِيرُ رَقَبَةٍ}، وَأَىّ الرِّقَابِ أَزْكَى؟
Narrated Abu Huraira:
The Prophet (ﷺ) said, "If somebody manumits a Muslim slave, Allah will save from the Fire every part of his body for freeing the corresponding parts of the slave's body, even his private parts will be saved from the Fire) because of freeing the slave's private parts."
Reference: Sahih al-Bukhari 6715
In-book reference: Book 84, Hadith 8
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 8, Book 79, Hadith 706