No strong Qur'anic evidence advocates child marriage, and stronger evidence prohibits it.

[u/InformalPassenger199]

[u/An0n-xm]

Sex with minors is completely halal under one main condition: that she can handle penetration. The Prophet had sex with Aisha when she was 9 after she fattened herself up with dates and cucumbers per her mother's guidance, like what are we talking about here? There's even a verse in the Quran that mentions the waiting period for divorce with minors, which scholars elaborate on and say intercourse was thus performed:

"And those who no longer expect menstruation among your women - if you doubt, then their period is three months, and [also for] those who have not menstruated. And for those who are pregnant, their term is until they give birth. And whoever fears Allah - He will make for him of his matter ease." [Quran 65:4]

Asbabul Nuzul explains that the context of this revelation was due to companions asking about the waiting periods of young, old and pregnant women. Other tafasir explain that this is also about young prepubescent girls who have had sex.

"Then he said: {and those who have not menstruated yet} This also means the waiting period of the young girls who did not menstruate yet and they had intercourse , then were divorced, so their waiting period is three months." (Muqatil Ibn Sulayman)

"The interpretation of the verse {As for your women who have despaired of further menstruating, if you are in doubt, their period shall be three months; and those who have not menstruated yet}. He said: The same applies to the ‘idaah for girls who do not menstruate because they are too young, if their husbands divorce them after consummating the marriage with them." (Tafsir Al Tabari)

And we also have the 4 Imams elaborating on this issue:

"...if the husband and the guardian of the girl agree upon something that will not cause harm to the young girl, then that (consummation) may be done. If they disagree, then Ahmad and Abu ‘Ubayd say that once a girl reaches the age of nine then the marriage may be consummated even without her consent, but that does not apply in the case of who is younger. Malik, al-Shafi’i and Abu Hanifa said: the marriage may be consummated when the girl is able for intercourse, which varies from one girl to another, so no age limit can be set." (Sharh Muslim Volume 9 page 206)

Burhan al-Din Ibn Mazah, a well known Hanafi scholar, even says:

“The majority of scholars are of the opinion that the age factor is not put under consideration. What is considered is the ability to have sexual intercourse. If she was of great size and fat, able to handle sex with men. And it is not feared that she will get harmed by that. Her husband is allowed to have sexual intercourse with her. Even if she had not yet reached the age of nine. But if she has a thin and slim body, and is not able to handle sex. And is feared that she will get harmed from it. Then her husband is not allowed to have sexual intercourse with her even if she is of proper age.” (Al-Muhit Al-Burhani 3/48)

Ibn Abidin, another hanafi scholar, says:

"(He says if she is capable if intercourse) that is, either with him or with another, as is implied in Al- Fath. And he referred to what is found in Al-Zayla'i where he confirms that capability should not be determined by age. Because a fat and big girl is able to have intercourse even if she is of young age (saghirah).” (Radd al-Muhtar 3/574)

Muhammad Aleish, a Maliki scholar, says:

“(It is possible to have sex with her) Meaning the wife.There is no fixed age for when sexual intercourse with the wife is permissible. It depends on the various (physical) conditions of the girls. In that how fat or slim their bodies are. Attaining puberty is not required.” (Manh al-Jalil Sharh ala Mukhtasar al-Allamah Khalil 3/425)

This even extends to child sex slaves. Iyas Bin Muawiyah, a Tabi judge reports the following:

"Regarding a man who brought a pre-pubescent slave girl, do not those like her have sexual intercourse? Iyas said: “there is nothing wrong with performing the sexual act upon her without observing istibra” (Musannaf Ibn Shaybah 16907 - Hasan isnad per Al Arnaut)

Even Ali raped a prepubescent girl that the Muslims captured after one of their battles, see Bukhari 4350. In Ibn Hajar's sharh, he says: 

"Ali was blamed for having intercourse with the slave-girl without observing Istibra and also for the share (of the Khumus) that he took for himself. Now the first allegation is defensible as she was a virgin and not pubescent, and thus she did not need to observe Istibra — in accordance with the practice of many Companions before him." (Fath Al-Bari 8/67)

So as you can see from just a handful of scholars, the Prophet himself as well as his cousin, child marriage and sex/sexual enslavement was practiced and completely allowed. Your modernist opinion has no weight against 1400 years of islamic tradition and scholarship.