It is narrated from an Ansari companion that he brought an Abyssinian slave woman and said to the Prophet (peace be upon him): O Messenger of Allah! It is obligatory upon me to free a Muslim slave. If you think she is a believer, I will set her free. The Prophet (peace be upon him) asked the slave woman: Do you testify that there is no god but Allah? She said: Yes. The Prophet (peace be upon him) said: Do you testify that I am the Messenger of Allah? She said: Yes. The Prophet (peace be upon him) said: Do you believe in being resurrected after death? She said: Yes. The Prophet (peace be upon him) said: Set her free.