What does « Right hand / Blessing » mean in the Quran?

And whoever among you cannot [find] the means to marry free, believing women, then [he may marry] from those whom your right hands possess of believing slave girls. And Allah is most knowing about your faith. You [believers] are of one another. So marry them with the permission of their people and give them their due compensation according to what is acceptable. [They should be] chaste, neither [of] those who commit unlawful intercourse randomly nor those who take [secret] lovers. But once they are sheltered in marriage, if they should commit adultery, then for them is half the punishment for free [unmarried] women. This [allowance] is for him among you who fears sin, but to be patient is better for you. And Allah is Forgiving and Merciful.

And for all, We have made heirs to what is left by parents and relatives. And to those whom your oaths have bound [to you] - give them their share. Indeed Allah is ever, over all things, a Witness.

Worship Allah and associate nothing with Him, and to parents do good, and to relatives, orphans, the needy, the near neighbor, the neighbor farther away, the companion at your side, the traveler, and those whom your right hands possess. Indeed, Allah does not like those who are self-deluding and boastful.

And those who believe will say, "Are these the ones who swore by Allah their strongest oaths that indeed they were with you?" Their deeds have become worthless, and they have become losers.

Allah will not impose blame upon you for what is meaningless in your oaths, but He will impose blame upon you for [breaking] what you intended of oaths. So its expiation is the feeding of ten needy people from the average of that which you feed your [own] families or clothing them or the freeing of a slave. But whoever cannot find [or afford it] - then a fast of three days [is required]. That is the expiation for oaths when you have sworn. But guard your oaths. Thus does Allah make clear to you His verses that you may be grateful.

That is more likely that they will give testimony according to its [true] objective, or [at least] they would fear that [other] oaths might be taken after their oaths. And fear Allah and listen; and Allah does not guide the defiantly disobedient people.

And they swear by Allah their strongest oaths that if a sign came to them, they would surely believe in it. Say, "The signs are only with Allah." And what will make you perceive that even if a sign came, they would not believe.

Then I will come to them from before them and from behind them and on their right and on their left, and You will not find most of them grateful [to You]."

And if they break their oaths after their treaty and defame your religion, then fight the leaders of disbelief, for indeed, there are no oaths [sacred] to them; [fight them that] they might cease.

Would you not fight a people who broke their oaths and determined to expel the Messenger, and they had begun [the attack upon] you the first time? Do you fear them? But Allah has more right that you should fear Him, if you are [truly] believers.

And they swear by Allah their strongest oaths [that] Allah will not resurrect one who dies. But yes - [it is] a true promise [binding] upon Him, but most of the people do not know.

Have they not considered what things Allah has created? Their shadows incline to the right and to the left, prostrating to Allah, while they are humble.

And Allah has favored some of you over others in provision. But those who were favored would not hand over their provision to those whom their right hands possess so they would be equal to them therein. Then is it the favor of Allah they reject?

And fulfill the covenant of Allah when you have taken it, [O believers], and do not break oaths after their confirmation while you have made Allah, over you, a witness. Indeed, Allah knows what you do.

And do not be like she who untwisted her spun thread after it was strong [by] taking your oaths as [means of] deceit between you because one community is more plentiful [in number or wealth] than another community. Allah only tries you thereby. And He will surely make clear to you on the Day of Resurrection that over which you used to differ.

And do not take your oaths as [means of] deceit between you, lest a foot slip after it was [once] firm, and you would taste evil [in this world] for what [people] you diverted from the way of Allah, and you would have [in the Hereafter] a great punishment.

[Mention, O Muhammad], the Day We will call forth every people with their record [of deeds]. Then whoever is given his record in his right hand - those will read their records, and injustice will not be done to them, [even] as much as a thread [inside the date seed].

And [had you been present], you would see the sun when it rose, inclining away from their cave on the right, and when it set, passing away from them on the left, while they were [laying] within an open space thereof. That was from the signs of Allah. He whom Allah guides is the [rightly] guided, but he whom He leaves astray - never will you find for him a protecting guide.

And you would think them awake, while they were asleep. And We turned them to the right and to the left, while their dog stretched his forelegs at the entrance. If you had looked at them, you would have turned from them in flight and been filled by them with terror.

And We called him from the side of the mount at [his] right and brought him near, confiding [to him].

And what is that in your right hand, O Moses?"

And throw what is in your right hand; it will swallow up what they have crafted. What they have crafted is but the trick of a magician, and the magician will not succeed wherever he is."

O Children of Israel, We delivered you from your enemy, and We made an appointment with you at the right side of the mount, and We sent down to you manna and quails,

Except from their wives or those their right hands possess, for indeed, they will not be blamed -

And tell the believing women to reduce [some] of their vision and guard their private parts and not expose their adornment except that which [necessarily] appears thereof and to wrap [a portion of] their headcovers over their chests and not expose their adornment except to their husbands, their fathers, their husbands' fathers, their sons, their husbands' sons, their brothers, their brothers' sons, their sisters' sons, their women, that which their right hands possess, or those male attendants having no physical desire, or children who are not yet aware of the private aspects of women. And let them not stamp their feet to make known what they conceal of their adornment. And turn to Allah in repentance, all of you, O believers, that you might succeed.