The Prophet ﷺ said, "Whoever frees his share in a slave must complete the freeing of what remains from his own wealth, if he has wealth sufficient to cover the price of the slave."
أخبرنا نوح بن حبيب قال أنبأنا عبد الرزاق قال أنبأنا معمر عن الزهري
أن النبي ﷺ قال من أعتق شركا له في عبد أتم ما بقي في ماله إن كان له مال يبلغ ثمن العبد
Reported by Muslim, in the Book of Oaths, Chapter: Whoever frees his share in a slave, hadith no. 51/1501, after hadith no. 1667, from the hadith of Abdul-Razzaq through this chain, and it is in Kubra, hadith no. 6297.