What does « To send / Messenger » mean in the Quran?

Our Lord, and send among them a messenger from themselves who will recite to them Your verses and teach them the Book and wisdom and purify them. Indeed, You are the Exalted in Might, the Wise."

And thus we have made you a just community that you will be witnesses over the people and the Messenger will be a witness over you. And We did not make the qiblah which you used to face except that We might make evident who would follow the Messenger from who would turn back on his heels. And indeed, it is difficult except for those whom Allah has guided. And never would Allah have caused you to lose your faith. Indeed Allah is, to the people, Kind and Merciful.

Just as We have sent among you a messenger from yourselves reciting to you Our verses and purifying you and teaching you the Book and wisdom and teaching you that which you did not know.

Or do you think that you will enter Paradise while such [trial] has not yet come to you as came to those who passed on before you? They were touched by poverty and hardship and were shaken until [even their] messenger and those who believed with him said, "When is the help of Allah?" Unquestionably, the help of Allah is near.

These are the verses of Allah which We recite to you, [O Muhammad], in truth. And indeed, you are from among the messengers.

Those messengers - some of them We caused to exceed others. Among them were those to whom Allah spoke, and He raised some of them in degree. And We gave Jesus, the Son of Mary, clear proofs, and We supported him with the Pure Spirit. If Allah had willed, those [generations] succeeding them would not have fought each other after the clear proofs had come to them. But they differed, and some of them believed and some of them disbelieved. And if Allah had willed, they would not have fought each other, but Allah does what He intends.

And if you do not, then be informed of a war [against you] from Allah and His Messenger. But if you repent, you may have your principal - [thus] you do no wrong, nor are you wronged.

The Messenger has believed in what was revealed to him from his Lord, and [so have] the believers. All of them have believed in Allah and His angels and His books and His messengers, [saying], "We make no distinction between any of His messengers." And they say, "We hear and we obey. [We seek] Your forgiveness, our Lord, and to You is the [final] destination."

Say, "Obey Allah and the Messenger." But if they turn away - then indeed, Allah does not like the disbelievers.

And [make him] a messenger to the Children of Israel, [who will say], 'Indeed I have come to you with a sign from your Lord in that I design for you from clay [that which is] like the form of a bird, then I breathe into it and it becomes a bird by permission of Allah. And I cure the blind and the leper, and I give life to the dead - by permission of Allah. And I inform you of what you eat and what you store in your houses. Indeed in that is a sign for you, if you are believers.

Our Lord, we have believed in what You revealed and have followed the messenger Jesus, so register us among the witnesses [to truth]."

And [recall, O People of the Scripture], when Allah took the covenant of the prophets, [saying], "Whatever I give you of the Scripture and wisdom and then there comes to you a messenger confirming what is with you, you [must] believe in him and support him." [Allah] said, "Have you acknowledged and taken upon that My commitment?" They said, "We have acknowledged it." He said, "Then bear witness, and I am with you among the witnesses."

How shall Allah guide a people who disbelieved after their belief and had witnessed that the Messenger is true and clear signs had come to them? And Allah does not guide the wrongdoing people.

And how could you disbelieve while to you are being recited the verses of Allah and among you is His Messenger? And whoever holds firmly to Allah has [indeed] been guided to a straight path.

And obey Allah and the Messenger that you may obtain mercy.

Muhammad is not but a messenger. [Other] messengers have passed on before him. So if he was to die or be killed, would you turn back on your heels [to unbelief]? And he who turns back on his heels will never harm Allah at all; but Allah will reward the grateful.

[Remember] when you [fled and] climbed [the mountain] without looking aside at anyone while the Messenger was calling you from behind. So Allah repaid you with distress upon distress so you would not grieve for that which had escaped you [of victory and spoils of war] or [for] that which had befallen you [of injury and death]. And Allah is [fully] Acquainted with what you do.

Certainly did Allah confer [great] favor upon the believers when He sent among them a Messenger from themselves, reciting to them His verses and purifying them and teaching them the Book and wisdom, although they had been before in manifest error.

Those [believers] who responded to Allah and the Messenger after injury had struck them. For those who did good among them and feared Allah is a great reward -

Allah would not leave the believers in that [state] you are in [presently] until He separates the evil from the good. Nor would Allah reveal to you the unseen. But [instead], Allah chooses of His messengers whom He wills, so believe in Allah and His messengers. And if you believe and fear Him, then for you is a great reward.

[They are] those who said, "Indeed, Allah has taken our promise not to believe any messenger until he brings us an offering which fire [from heaven] will consume." Say, "There have already come to you messengers before me with clear proofs and [even] that of which you speak. So why did you kill them, if you should be truthful?"

Then if they deny you, [O Muhammad] - so were messengers denied before you, who brought clear proofs and written ordinances and the enlightening Scripture.

Our Lord, and grant us what You promised us through Your messengers and do not disgrace us on the Day of Resurrection. Indeed, You do not fail in [Your] promise."

These are the limits [set by] Allah, and whoever obeys Allah and His Messenger will be admitted by Him to gardens [in Paradise] under which rivers flow, abiding eternally therein; and that is the great attainment.

And whoever disobeys Allah and His Messenger and transgresses His limits - He will put him into the Fire to abide eternally therein, and he will have a humiliating punishment.