Did scholars define a limitation of concubines a man could have?

Question

While verse (4:3):

And if you fear that you will not deal justly with the orphan girls, then marry those that please you of [other] women, two or three or four. But if you fear that you will not be just, then [marry only] one or those your right hand possesses. That is more suitable that you may not incline [to injustice].

gives a limitation on the amount of wives a man can be simultaneously married to.

Just out of curiosity I'd like to know whether this applies/applied^● also to concubines (slave girls) or if there is any ruling or a consensus about a ruling giving a limitation of concubines a man could have?

● _{IMO slavery is no more legal even as all Muslim states have officially declared it as such}

Answer 1

I haven't come across any reference mentioning a legal limitation on the number of slaves. The following are some references that negate any limit, the English text is my personal translation and may contain paraphrasing, mistakes and omissions.

ولا خلاف أن له أن يجمع من العدد من شاء بملك اليمين

There is no difference of opinion that one may keep whatever number they wish of slaves

^{— Tafsir al-Jassas}

يعني السراري لأنه لا يلزم فيهن من الحقوق ما يلزم في الحرائر ، ولا قسم لهن ، ولا وقف في عددهن

Meaning female slaves, for regarding them the same rights are not obligatory as are the obligatory rights regarding free women. There is no equitable distribution between them and no restriction on their number

^{— Tafsir al-Baghawy}

لا يتحدد ما يحل للرجل من السراري بأربع ولا بعدد معين ولو كان عنده من الزوجات واحدة فأكثر إلى أربع أو لم يكن جاز له أن يتسرى بما شاء من الجواري

There is no limit on the number of female slaves. A man can keep as many slaves as he wants, be they four or more. Whether he has one to four wives or is not married at all. In all cases he can keep as many female slaves as he wants.

^{— الموسوعة الفقهية الكويتية}

4:3 has not mentioned limits regarding the number slaves, while mentioning limits regarding the number of wives. So it is inferable that there is no limit as otherwise it would have been mentioned.

The verse has commanded to limit oneself to slaves when one can not do justice to even one wife. This means that a person does not have the same obligations to their slaves as they do to their wives.

The verse has limited the number of wives based on the husband's capacity to observe justice between them: He has to provide each with adequate maintenance and lodging, and is required to provide them with companionship and to equally divide his time between them. Having multiple wives makes it difficult to give each their share.

On the other hand, a person does not owe such obligations to a slave, so there is no limit on how many he can have.