Chapter on Freedom
Man Lā Yaḥḍuruh al-Faqīh|Volume 3|Book 1|Chapter 51
وَ رُوِيَ عَنْ سَيْفِ بْنِ عَمِيرَةَ قَالَ: سَأَلْتُ أَبَا عَبْدِ اَللَّهِ عَلَيْهِ اَلسَّلاَمُ أَ يَجُوزُ لِلْمُسْلِمِ أَنْ يُعْتِقَ مَمْلُوكاً مُشْرِكاً قَالَ "لاَ".
It is narrated from Saif bin Amira, who said: "I asked Abu Abdullah عليه السلام, 'Is it permissible for a Muslim to free a slave who is a polytheist?'" Imam عليه السلام said: "No."
- Ṣaḥīḥ al-Faqīh