"Whoever sets free his share of a slave should set him free completely from his own wealth, if he has enough wealth to cover the price of the slave." (Using translation from Nasāʾī 4698)  

أَنَّ النَّبِيَّ ﷺ قَالَ مَنْ أَعْتَقَ شِرْكًا لَهُ فِي عَبْدٍ أُتِمَّ مَا بَقِيَ فِي مَالِهِ إِنْ كَانَ لَهُ مَالٌ يَبْلُغُ ثَمَنَ الْعَبْدِ  

"The Messenger of Allah said: 'Whoever sets free his share of a slave, and he has sufficient wealth to set him free completely by paying the price of the slave, then he should set him free with his own wealth."' (Using translation from Nasāʾī 4699)  

قَالَ رَسُولُ اللهِ ﷺ «مَنْ أَعْتَقَ شِرْكًا لَهُ فِي مَمْلُوكٍ وَكَانَ لَهُ مِنَ الْمَالِ مَا يَبْلُغُ ثَمَنَهُ بِقِيمَةِ الْعَدْلِ فَهُوَ عَتِيقٌ مِنْ مَالِهِ»