Hazrat Mujahid (may Allah have mercy on him) was asked whether zihar (a form of divorce) is valid with a slave woman. He considered it nothing (i.e., not valid). I said: "Allah the Exalted says: «الَّذِينَ يُظَاهِرُونَ مِنْ نِسَائِهِمْ» Is she not included among women?" He replied: "Allah said: «وَاسْتَشْهِدُوا شَهِيدَيْنِ مِنْ رِجَالِكُمْ» So are slaves not men? Then is the testimony of slaves permissible?"