Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "Whoever frees his share in a slave, it is binding on him to free the rest of him as well. If that person has no wealth, the slave will work to earn his value."
Imam al-Tabarani recorded this narration in al-Mu'jam al-Awsat; its chain contains a narrator, Muhammad bin Ishaq al-Marwazi, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب العتق / 7290