Muslim apologists try to prove that Mariya Qibtiyyah (رضي الله عنها) was the wife of The Prophet ﷺ thereby trying to defend the honour of our beloved Prophet ﷺ.
However this is far from the truth and it is well established by proofs that Mariya Qibtiyyah was a slave girl of The Prophet ﷺ, and having a slave girl is not something disliked or prohibited.
Allah allows The Muslims to have slave girls (of course subjected to certain conditions):
وَالَّذِينَ هُمْ لِفُرُوجِهِمْ حَافِظُونَ
And those who guard their private parts
-Sura Al-Ma’arij, Ayah 29
إِلَّا عَلَىٰ أَزْوَاجِهِمْ أَوْ مَا مَلَكَتْ أَيْمَانُهُمْ فَإِنَّهُمْ غَيْرُ مَلُومِينَ
Except from their wives or those their right hands possessions, for indeed, they are not to be blamed –
-Sura Al-Ma’arij, Ayah 30
(Sahih International)
Right hand possesions are nothing but slave girls.
See a detailed answer on the issue of Mariya Qibtiyyah here.
Saheehus-Seerah 