(7) باب إِذَا قَالَ رَجُلٌ لِعَبْدِهِ هُوَ لِلَّهِ وَنَوَى الْعِتْقَ، وَالإِشْهَادُ فِي الْعِتْقِ
Narrated Qais:
When Abu Huraira accompanied by his slave came intending to embrace Islam, they lost each other on the way. (When the slave showed up) Abu Huraira said (to the Prophet), "I make you witness that the slave is free for Allah's Cause."
Reference: Sahih al-Bukhari 2532
In-book reference: Book 49, Hadith 17
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 46, Hadith 709