Regarding the expiation for zihār, Allah says: “Those who pronounce zihār upon their wives, then go back on what they have said, must free a slave before the two of them touch one another.” [al-Mujādilah: 3] This is what appears in the Quran. The expiation for intercourse during Ramadan is established in the sunnah: the Prophet, may Allah’s peace and blessings be upon him, said to the man, “Can you find a slave?” He replied, “No.” (1) He did not say, “a believing slave.” Thus, there are three texts in which faith is not stipulated, and one text in which it is stipulated. This one text differs from the rest in that it is more serious than them in one respect, though less serious in another. The one in which faith is stipulated is the expiation for killing. It is more serious than the other acts entailing expiation: more serious than zihār, intercourse during the daytime in Ramadan, and breaking an oath. Yet it is less serious than them in one respect, because it is accidental whereas these are deliberate. In any case, the author, may Allah have mercy on him, stipulates faith in all expiations.
His evidence is that Allah stipulated faith in the expiation for killing, so the remaining cases are analogized to it, because the required act is one and the same: freeing a slave. Furthermore, it is authentically reported that Mu‘āwiyah ibn al-Ḥakam, may Allah be pleased with him, said: “O Messenger of Allah, I have a slave-girl whom I became angry with one day and slapped. I wish to free her.” He asked her, “Where is Allah?” She replied, “In heaven.” He asked, “Who am I?” She replied, “You are the Messenger of Allah.” He said, “Free her, for she is a believer.” (2) The Prophet, may Allah’s peace and blessings be upon him, did not inquire what kind of slave he was required to free. If a disbeliever may not be emancipated even outside an expiation, then this is even more so in the case of an expiation. This indicates that faith is a condition in all cases where freeing a slave is obligatory. We may also say—