Answer
Salam Dear Sister,
Thank you for your question and for contacting Ask About Islam.
Let me quote the two verses you referred to in your question.
Allah says what means:
{O Prophet, indeed We have made lawful to you your wives to whom you have given their due compensation and those your right hand possesses from what Allah has returned to you [of captives] and the daughters of your paternal uncles and the daughters of your paternal aunts and the daughters of your maternal uncles and the daughters of your maternal aunts who emigrated with you and a believing woman if she gives herself to the Prophet [and] if the Prophet wishes to marry her, [this is] only for you, excluding the [other] believers. We certainly know what We have made obligatory upon them concerning their wives and those their right hands possess, [but this is for you] in order that there will be upon you no discomfort. And ever is Allah Forgiving and Merciful.} (Al-Ahzab 33:5)
We also read:
{Not lawful to you, [O Muhammad], are [any additional] women after [this], nor [is it] for you to exchange them for [other] wives, even if their beauty were to please you, except what your right hand possesses. And ever is Allah, over all things, an Observer.} (Al-Ahzab 33:52)
In our 21st century, it is very weird to talk about the issue of having female slaves or captives or having sex with them. The phenomenon of having female slaves is as very old as the birth of Islam itself. It was even widespread before the advent of Islam. Islam came while it was very common among the people in Arabia to have female slaves.
A female salve is a woman who is owned by her master either because of slavery or because of being taken captive during wars.
At that time, the master had the right to have sex with his slave woman but she was not entitled to any rights. And if it happened this relation resulted in a child, this child was not recognized. But when Islam came, it regulated this relation.
The child was considered free and recognized as the child of the master and no more his slave. Also the woman would not be categorized as a slave but she was called umm walador mother of a free child. This gave her the right to be set free after the death of her master; the father of her child.
This is what Islam offered to organize this relation and give everyone his due rights.
As for slavery and how Islam drained all it sources, we recommend the following answers for reading:
As for the number of the female slaves of concubines that the Prophet (peace and blessings be upon him) had, let’s agree first that this was normal at that time and it was accepted even among the Prophet’s wives and his Companions.
Ibn Qayyim al-Jawziyyah said in his Zad al-Ma`ad:
“Abu `Ubaydah said: He (the Prophet) had four (concubines): Mariyah, who was the mother of his son Ibrahim; Rayhanah; another beautiful slave woman whom he acquired as a prisoner of war; and a slave woman who was given to him by Zaynab bint Jahsh.”
To prove that this practice was normal, Prophet Ibrahim (peace be upon him) had Lady Hajar as his concubine. Also Prophet Soliman (peace be upon him) is reported to have about 300 concubines.
Now let me quote for you what Prophet Muhammad had to say about slaves and their rights. Slaves can be interpreted to mean house-maids or the servants who help us at home:
“Your servants and your slaves are your brothers. Anyone who has slaves should give them from what he eats and wears. He should not charge them with work beyond their capabilities. If you must set them to hard work, in any case I advise you to help them.” (Al-Bukhari)
Ali ibn Abi Talib (may Allah be pleased with him) reported that the last words of the Prophet were:
“The prayer! The prayer! Fear Allah concerning your slaves!” (Al-Bukhari in his Al-Adab al-Mufrad)
Jabir ibn ‘Abdullah (may Allah be pleased with him) said:
“The Prophet advised that slaves should be well-treated. He said, ‘Feed them from what you eat and clothe them from what you wear. Do not punish what Allah has created.’ (Al-Bukhari in his Al-Adab al-Mufrad)
We hope this answers your question.
Salam and keep in touch.