The marriage of the Prophet ﷺ to 'Ā'isha was 100% legitimate from an Islamic point of view as she was already a woman at the time of marriage, and all the conditions of marriage were fulfilled. She and her family blessed the marriage, as did the Prophet.
The Age of 'Ā'isha at the Time of Her Marriage
As 'Ā'isha herself narrated her story, she was betrothed at the age of six years, and the marriage was consummated at the age of nine years:
حَدَّثَنَا مُعَلَّى بْنُ أَسَدٍ، حَدَّثَنَا وُهَيْبٌ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم تَزَوَّجَهَا وَهْىَ بِنْتُ سِتِّ سِنِينَ، وَبَنَى بِهَا وَهْىَ بِنْتُ تِسْعِ سِنِينَ. قَالَ هِشَامٌ وَأُنْبِئْتُ أَنَّهَا كَانَتْ عِنْدَهُ تِسْعَ سِنِينَ
Narrated 'Aisha: that the Prophet (ﷺ) married her when she was six years old and he consummated his marriage when she was nine years old. Hisham said: I have been informed that 'Aisha remained with the Prophet (ﷺ) for nine years (i.e. till his death).
— Sahih al-Bukhari, Book 67, Hadith 70
In another hadith, the marriage year is connected to the Hijra to Medina and the death of Khadīja:
حَدَّثَنِي عُبَيْدُ بْنُ إِسْمَاعِيلَ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، قَالَ تُوُفِّيَتْ خَدِيجَةُ قَبْلَ مَخْرَجِ النَّبِيِّ صلى الله عليه وسلم إِلَى الْمَدِينَةِ بِثَلاَثِ سِنِينَ، فَلَبِثَ سَنَتَيْنِ أَوْ قَرِيبًا مِنْ ذَلِكَ، وَنَكَحَ عَائِشَةَ وَهْىَ بِنْتُ سِتِّ سِنِينَ، ثُمَّ بَنَى بِهَا وَهْىَ بِنْتُ تِسْعِ سِنِينَ
Narrated Hisham's father: Khadija died three years before the Prophet (ﷺ) departed to Medina. He stayed there for two years or so and then he married 'Aisha when she was a girl of six years of age, and he consumed that marriage when she was nine years old.
— Sahih al-Bukhari, Book 63, Hadith 122
There are numerous other hadiths that were widely documented in almost all books of hadith about nine years being the age at which the marriage was consummated, irrespective of what some apologetics claim.
Conclusion. 'Ā'isha was six years old at the time of her betrothal and nine years old at the time of consummation of the marriage. There is no dispute to be accepted (khilāf mu'tabar) about this matter.
The Story of 'Ā'isha's Marriage
Prior to her betrothal to the Prophet, 'Ā'isha was betrothed to Jubayr ibn Mut'im ibn 'Adi. As per At-Tabarani in his book Al-Mu'jam al-Kabīr:
حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ الْحَضْرَمِيُّ، ثنا عَبْدُ اللَّهِ بْنُ عُمَرَ بْنِ أَبَانَ، ثنا أَبُو أُسَامَةَ، عَنِ الأَجْلَحِ، عَنِ ابْنِ أَبِي مُلَيْكَةَ، قَالَ: خَطَبَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَائِشَةَ إِلَى أَبِي بَكْرٍ، وَكَانَ أَبُو بَكْرٍ قَدْ زَوَّجَهَا جُبَيْرَ بْنَ مُطْعِمٍ، فَخَلَعَهَا مِنْهُ، فَزَوَّجَهَا رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَهِيَ ابْنَةُ سِتِّ سِنِينَ، تَرَكَهَا ثَلاثَ سِنِينَ، ثُمَّ بَنَى بِهَا وَهِيَ بِنْتُ تِسْعِ سِنِينَ
— NOTE: My own translation, so treat with care:
Narrated to Mohammad ibn 'Abdullah al-Hadrami through 'Abdullah ibn 'Umar ibn Abān through Abu Usāma through Al-Ajlah through Ibn Abu Mulaika: "The Messenger of Allah ﷺ betrothed 'Ā'isha through Abi Bakr. Abu Bakr had betrothed her to Jubayr ibn Mut'im, then he voided the betrothal, then he betrothed her to the Messenger of Allah ﷺ when she was six years old. He let her [live with her parents] for three years, then they consummated their marriage when she was nine years old.
— Al-Mu'jam al-Kabīr, Hadith 18626
The story of her betrothal to Jubayr ibn Mut'im is documented in Musnad Ahmad, Vol. 43 among other books. Abu Bakr, 'Ā'isha's father, betrothed his daughter to Jubayr (Mut'im's son) when she was one year old. Khawlah bint Hakim, after the death of Khadija, went to Sawda bint Zam'a (just widowed from As-Sakrān ibn Amr) to see if she would marry the Prophet. She also approached Umm Ruman, the wife of Abu Bakr and the mother of 'Ā'isha. Umm Ruman mentioned this to Abi Bakr, who responded that he had promised her to the son of Mut'im ibn 'Adi and he would not go back on his word unless Mut'im annulled the betrothal.
Abu Bakr visited Mut'im while his wife, Umm Al-Fata, was present. She told Aba Bakr, "Perhaps you would get our friend [Jubayr] out of his religion and into yours if he marries from your family." When Abu Bakr inquired about Mut'im's stance, he simply replied that she repeated what she heard. Abu Bakr consulted Umm Ruman about the annulment. She said: "This is your daughter, 'Ā'isha, and Allah removed Jubayr and his family from her way, so marry her the Messenger of Allah ﷺ and she will get rewards and blessings." Abu Bakr asked Khawlah to invite the Prophet ﷺ over to a betrothal. When Khawla told the Prophet ﷺ about marrying 'Ā'isha, he agreed as he had had a dream about marrying her earlier on:
عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ لَهَا: أُرِيتُكِ فِي الْمَنَامِ مَرَّتَيْنِ، أَرَى أَنَّكِ فِي سَرَقَةٍ مِنْ حَرِيرٍ وَيَقُولُ هَذِهِ امْرَأَتُكَ فَاكْشِفْ عَنْهَا فَإِذَا هِيَ أَنْتِ فَأَقُولُ إِنْ يَكُ هَذَا مِنْ عِنْدِ اللَّهِ يُمْضِهِ
Narrated 'Aisha: That the Prophet (ﷺ) said to her, "You have been shown to me twice in my dream. I saw you pictured on a piece of silk and some-one said (to me). 'This is your wife.' When I uncovered the picture, I saw that it was yours. I said, 'If this is from Allah, it will be done."
— Sahih al-Bukhari, Book 63, Hadith 121
'Ā'isha narrated the rest of the story herself in the hadith below in Sahih Muslim:
حَدَّثَنَا أَبُو كُرَيْبٍ، مُحَمَّدُ بْنُ الْعَلاَءِ حَدَّثَنَا أَبُو أُسَامَةَ، ح وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي، شَيْبَةَ قَالَ وَجَدْتُ فِي كِتَابِي عَنْ أَبِي أُسَامَةَ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، قَالَتْ تَزَوَّجَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم لِسِتِّ سِنِينَ وَبَنَى بِي وَأَنَا بِنْتُ تِسْعِ سِنِينَ. قَالَتْ فَقَدِمْنَا الْمَدِينَةَ فَوُعِكْتُ شَهْرًا فَوَفَى شَعْرِي جُمَيْمَةً فَأَتَتْنِي أُمُّ رُومَانَ وَأَنَا عَلَى أُرْجُوحَةٍ وَمَعِي صَوَاحِبِي فَصَرَخَتْ بِي فَأَتَيْتُهَا وَمَا أَدْرِي مَا تُرِيدُ بِي فَأَخَذَتْ بِيَدِي فَأَوْقَفَتْنِي عَلَى الْبَابِ. فَقُلْتُ هَهْ هَهْ. حَتَّى ذَهَبَ نَفَسِي فَأَدْخَلَتْنِي بَيْتًا فَإِذَا نِسْوَةٌ مِنَ الأَنْصَارِ فَقُلْنَ عَلَى الْخَيْرِ وَالْبَرَكَةِ وَعَلَى خَيْرِ طَائِرٍ. فَأَسْلَمَتْنِي إِلَيْهِنَّ فَغَسَلْنَ رَأْسِي وَأَصْلَحْنَنِي فَلَمْ يَرُعْنِي إِلاَّ وَرَسُولُ اللَّهِ صلى الله عليه وسلم ضُحًى فَأَسْلَمْنَنِي إِلَيْهِ
'A'isha (Allah be pleased with her) reported: Allah's Messenger (ﷺ) married me when I was six years old, and I was admitted to his house at the age of nine. She further said: We went to Medina and I had an attack of fever for a month, and my hair had come down to the earlobes. Umm Ruman (my mother) came to me and I was at that time on a swing along with my playmates. She called me loudly and I went to her and I did not know what she had wanted of me. She took hold of my hand and took me to the door, and I was saying: Ha, ha (as if I was gasping), until the agitation of my heart was over. She took me to a house, where had gathered the women of the Ansar. They all blessed me and wished me good luck and said: May you have share in good. She (my mother) entrusted me to them. They washed my head and embellished me and nothing frightened me. Allah's Messenger (may peace be upon him) came there in the morning, and I was entrusted to him.
— Sahih Muslim, Book 16, Hadith 81
The Prophet ﷺ waited for three years until 'Āisha reached puberty and was physically capable of consummating the marriage before doing so. When asked about it, 'Ā'isha confirmed that she had reached maturity:
قَالَتْ عَائِشَةُ: إِذَا بَلَغَتِ الجَارِيَةُ تِسْعَ سِنِينَ فَهِيَ امْرَأَةٌ
— NOTE: My own translation, so treat with care:
'Aisha narrated: "When the young girl [referring to herself] reached nine years of age, she is a woman."
— Sunnan At-Tirmidhi, Vol. 3, pp. 409
It was not uncommon for girls to reach puberty at nine years of age or earlier in the Arabian peninsula at the time. Ash-Shafi'i in a story — unrelated to the marriage of the Prophet ﷺ and 'Ā'isha — that was documented by Al-Bayhaqi in his Sunnan (Vol. 1, pp. 476) said that he saw in Yemen a grandmother at the age of 21. She got her menarche at the age of nine, and her first child at the age of 10. Her daughter, like her mother, got her menarche at the age of nine, and her first child at the age of 10. The age of menarche varies by geography, race, nutrition, environment, genes, etc.
There was indeed no objection to the marriage by any of the anti-Islamic lobby at the time: Quraish disbelievers, Persians, Romans, Jews, Christians, etc. The argument that there was no objection as it had not taken place is invalid. It was dealt verbally in the 1st century, then documented in writing in the books of hadith in 2nd-4th centuries A.H. Why is there no documented objection until recently? As for the claims of pedophilia, the definition is "for sexual activity with a prepubescent child or children" (see The ICD-10 Classification of Mental and Behavioural Disorders section F65.4 Paedophilia). As demonstrated above, 'Ā'isha was not a prepubescent child at the time of her marriage. Indeed, she was very young, but she was not a prepubescent child.
Conclusion. The marriage of the Prophet ﷺ to 'Ā'isha was recommended by others as it was then culturally acceptable to get married at a young age, even 'Ā'isha was already betrothed to another person prior to her engagement to the Prophet. The marriage was consummated after she had reached maturity and was Islamically fit to be married. Even by today's standards, this marriage would not be classified as pedophilia.
Legal Age of Marriage in Islam
There is no known disagreement among scholars that the age of accountability, either in front of Allah for one's actions or in front of the law in terms of taking command of one's decisions or being accountable for one's actions legally, varies by person as it is defined by reaching puberty:
عَنْ عَائِشَةَ رضى الله عنها أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ: رُفِعَ الْقَلَمُ عَنْ ثَلاَثَةٍ عَنِ النَّائِمِ حَتَّى يَسْتَيْقِظَ وَعَنِ الْمُبْتَلَى حَتَّى يَبْرَأَ وَعَنِ الصَّبِيِّ حَتَّى يَكْبَرَ
Narrated Aisha, Ummul Mu'minin: The Messenger of Allah (ﷺ) said: There are three (persons) whose actions are not recorded: a sleeper till he awakes, an idiot till he is restored to reason, and a boy till he reaches puberty.
— Sunan Abi Dawud, Book 40, Hadith 48
Reaching the age of puberty marks the development of one's physical ability, too, which is the end of childhood as per the following verse (and other verses — see 6:152, 17:34, 40:67, and 46:15, for example):
وَنُقِرُّ فِي الْأَرْحَامِ مَا نَشَاءُ إِلَىٰ أَجَلٍ مُّسَمًّى ثُمَّ نُخْرِجُكُمْ طِفْلًا ثُمَّ لِتَبْلُغُوا أَشُدَّكُمْ
And We settle in the wombs whom We will for a specified term, then We bring you out as a child, and then [We develop you] that you may reach your [time of] maturity.
— Surat Al-Hajj 22:5
Accordingly, reaching the age of puberty acts as one of the conditions of the consummation of marriage. The following verse tells us to test the orphans (an orphan is one that has not yet reached puberty — see when does someone stop being an orphan?) until they reach marriageable age, which is when they reach puberty:
وَابْتَلُوا الْيَتَامَىٰ حَتَّىٰ إِذَا بَلَغُوا النِّكَاحَ فَإِنْ آنَسْتُم مِّنْهُمْ رُشْدًا فَادْفَعُوا إِلَيْهِمْ أَمْوَالَهُمْ ۖ وَلَا تَأْكُلُوهَا إِسْرَافًا وَبِدَارًا أَن يَكْبَرُوا ۚ وَمَن كَانَ غَنِيًّا فَلْيَسْتَعْفِفْ ۖ وَمَن كَانَ فَقِيرًا فَلْيَأْكُلْ بِالْمَعْرُوفِ ۚ فَإِذَا دَفَعْتُمْ إِلَيْهِمْ أَمْوَالَهُمْ فَأَشْهِدُوا عَلَيْهِمْ ۚ وَكَفَىٰ بِاللَّهِ حَسِيبًا
And test the orphans [in their abilities] until they reach marriageable age. Then if you perceive in them sound judgment, release their property to them. And do not consume it excessively and quickly, [anticipating] that they will grow up. And whoever, [when acting as guardian], is self-sufficient should refrain [from taking a fee]; and whoever is poor - let him take according to what is acceptable. Then when you release their property to them, bring witnesses upon them. And sufficient is Allah as Accountant.
— Surat An-Nisa' 4:6
Another condition of marriage is the consent to be given by the bride, whether she was a virgin or she was previously married:
عَنِ ابْنِ عَبَّاسٍ أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ: الثَّيِّبُ أَحَقُّ بِنَفْسِهَا مِنْ وَلِيِّهَا وَالْبِكْرُ تُسْتَأْمَرُ وَإِذْنُهَا سُكُوتُهَا
Ibn Abbas (Allah be pleased with them) reported Allah's Messenger (ﷺ) as saying: "A woman who has been previously married (thayyib) has more right to her person than her guardian. And a virgin should be consulted, and her silence implies her consent.
— Sahih Muslim, Book 16, Hadith 79
Women cannot be married against their will. There is a story of a woman who was afraid that her guardian would offer her for marriage against her will. 'Abdur-Rahman and Mujammi' told her of the story of for Khansā' bint Khidām when the Prophet ﷺ annulled her marriage and considered void when her father offered her for marriage against her will:
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنِ الْقَاسِمِ، أَنَّ امْرَأَةً، مِنْ وَلَدِ جَعْفَرٍ تَخَوَّفَتْ أَنْ يُزَوِّجَهَا وَلِيُّهَا وَهْىَ كَارِهَةٌ فَأَرْسَلَتْ إِلَى شَيْخَيْنِ مِنَ الأَنْصَارِ عَبْدِ الرَّحْمَنِ وَمُجَمِّعٍ ابْنَىْ جَارِيَةَ قَالاَ فَلاَ تَخْشَيْنَ، فَإِنَّ خَنْسَاءَ بِنْتَ خِذَامٍ أَنْكَحَهَا أَبُوهَا وَهْىَ كَارِهَةٌ، فَرَدَّ النَّبِيُّ صلى الله عليه وسلم ذَلِكَ
Narrated Al-Qasim: A woman from the offspring of Ja'far was afraid lest her guardian marry her (to somebody) against her will. So she sent for two elderly men from the Ansar, 'AbdurRahman and Mujammi', the two sons of Jariya, and they said to her, "Don't be afraid, for Khansa' bint Khidam was given by her father in marriage against her will, then the Prophet (ﷺ) cancelled that marriage."
— Sahih al-Bukhari, Book 90, Hadith 16
The above verses and hadiths are among other evidence that made scholars agree that conditions of marriage include the consent of both parties, achieving puberty of both parties, and the physical ability of both parties to consummate their marriage (see Islam Q&A 2127 for more information).
Over the centuries, there was no predefined age of marriage in years, but rather in conditions, reaching puberty at the time of marriage being one. This predates the Islamic doctrine brought forth in the seventh century. In the Mishneh's Sefer Nashim (the Book of Women), the age of marriage is not defined in years; rather, as being fruitful and multiplying:
A man should not marry a barren women, an elderly woman, an aylonit or a minor who is not fit to bear a child unless he has already fulfilled the mitzvah of being fruitful and multiplying, or he has another wife with whom he can father children.
— Ishut 15:7
Similarly, in 1 Corinthians, marriage may take place "if she pass the flower of her age":
(36) But if any man think that he behaveth himself uncomely toward his virgin, if she pass the flower of her age, and need so require, let him do what he will, he sinneth not: let them marry. (37) Nevertheless he that standeth stedfast in his heart, having no necessity, but hath power over his own will, and hath so decreed in his heart that he will keep his virgin, doeth well. (38) So then he that giveth her in marriage doeth well; but he that giveth her not in marriage doeth better.
— 1 Corinthians 7:36-38 (KJV)
It is only in recent history that governments elected to use age defined in years to be one criterion of consent (viz. age of consent). However, I have not come across a scientific argument of how the age of consent is defined or why it is always being raised in the different countries. If one gets married at 18 years of age is acceptable, but at 17 years and 364 days of age is not? For example, why was the age of consent laws until early on in the 20th century only 10 years in a lot of places? It was even as low as seven years in the state of Delaware, which as per Wikipedia's article on age of consent reform, lowered the age of consent from 10 to 7 in 1871. The age seems to be decreasing in some countries to the age of eight. Could it be related to the age of puberty (see the BBC News article Why puberty now begins at seven says that "the normal age for a girl to begin to develop the first signs of puberty is 10 and above.") or is it unrelated? Hard to tell.
Conclusion. There is no predefined age of consent in Islam. The consummation of marriage is instead governed by conditions:
- Coming of age is upon reaching puberty
- Physical ability to consummate the marriage
- Approval of the marriage by the bride's parents and the bride.
When the Prophet ﷺ married 'Ā'isha, all the above conditions were fulfilled. Islamically, it was a valid marriage
Was the Marriage a Successful One?
In the story narrated by Jābir ibn 'Abdullah in Sahih Muslim (partially quoted below), when Abu Bakr and 'Umar visited the Prophet ﷺ and found all his wives sitting with him asking him for higher allowances, Abu Bakr slapped 'Ā'isha on her neck (and so did 'Umar with his daughter, Hafsa). Allah then revealed the verse of takhyīr, in which the wives of the Prophet ﷺ were given the choice to (a) be highly rewarded in this worldly life, or (b) stay with him without much pleasures of this worldly life and get rewarded in the Hereafter:
يَا أَيُّهَا النَّبِيُّ قُل لِّأَزْوَاجِكَ إِن كُنتُنَّ تُرِدْنَ الْحَيَاةَ الدُّنْيَا وَزِينَتَهَا فَتَعَالَيْنَ أُمَتِّعْكُنَّ وَأُسَرِّحْكُنَّ سَرَاحًا جَمِيلًا وَإِن كُنتُنَّ تُرِدْنَ اللَّهَ وَرَسُولَهُ وَالدَّارَ الْآخِرَةَ فَإِنَّ اللَّهَ أَعَدَّ لِلْمُحْسِنَاتِ مِنكُنَّ أَجْرًا عَظِيمًا
O Prophet, say to your wives, "If you should desire the worldly life and its adornment, then come, I will provide for you and give you a gracious release. But if you should desire Allah and His Messenger and the home of the Hereafter — then indeed, Allah has prepared for the doers of good among you a great reward."
— Surat Al-Ahzab 33:28-29
'Ā'isha was the first wife that the Prophet ﷺ approached, and asked her to consult her parents about staying with him or leaving him:
فَبَدَأَ بِعَائِشَةَ فَقَالَ: يَا عَائِشَةُ إِنِّي أُرِيدُ أَنْ أَعْرِضَ عَلَيْكَ أَمْرًا أُحِبُّ أَنْ لاَ تَعْجَلِي فِيهِ حَتَّى تَسْتَشِيرِي أَبَوَيْكِ. قَالَتْ وَمَا هُوَ يَا رَسُولَ اللَّهِ فَتَلاَ عَلَيْهَا الآيَةَ قَالَتْ أَفِيكَ يَا رَسُولَ اللَّهِ أَسْتَشِيرُ أَبَوَىَّ بَلْ أَخْتَارُ اللَّهَ وَرَسُولَهُ وَالدَّارَ الآخِرَةَ وَأَسْأَلُكَ أَنْ لاَ تُخْبِرَ امْرَأَةً مِنْ نِسَائِكَ بِالَّذِي قُلْتُ. قَالَ: لاَ تَسْأَلُنِي امْرَأَةٌ مِنْهُنَّ إِلاَّ أَخْبَرْتُهَا إِنَّ اللَّهَ لَمْ يَبْعَثْنِي مُعَنِّتًا وَلاَ مُتَعَنِّتًا وَلَكِنْ بَعَثَنِي مُعَلِّمًا مُيَسِّرًا "
He then went first to 'A'isha (Allah be pleased with her) and said: "I want to propound something to you, 'A'isha, but wish no hasty reply before you consult your parents." She said: "Messenger of Allah, what is that? He (the Holy Prophet) recited to her the verse, whereupon she said: Is it about you that I should consult my parents, Messenger of Allah? Nay, I choose Allah, His Messenger, and the Last Abode; but I ask you not to tell any of your wives what I have said." He replied: "Not one of them will ask me without my informing her. God did not send me to be harsh, or cause harm, but He has sent me to teach and make things easy."
— Sahih Muslim, Book 18, Hadith 39
Her response was swift and firm. She would not consult her parents, and she chose to stay with the Prophet. She had the chance to leave if she was traumatized by her marriage. It was her choice, fully, to stay with the Prophet. Not only so, but there are several accounts of her jealousy over the Prophet ﷺ from his other wives. When one of them sent food over while the Prophet ﷺ was in 'Ā'isha's house, she felt jealous and broke that food container:
حَدَّثَنَا عَلِيٌّ، حَدَّثَنَا ابْنُ عُلَيَّةَ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ، قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم عِنْدَ بَعْضِ نِسَائِهِ فَأَرْسَلَتْ إِحْدَى أُمَّهَاتِ الْمُؤْمِنِينَ بِصَحْفَةٍ فِيهَا طَعَامٌ، فَضَرَبَتِ الَّتِي النَّبِيُّ صلى الله عليه وسلم فِي بَيْتِهَا يَدَ الْخَادِمِ فَسَقَطَتِ الصَّحْفَةُ فَانْفَلَقَتْ، فَجَمَعَ النَّبِيُّ صلى الله عليه وسلم فِلَقَ الصَّحْفَةِ، ثُمَّ جَعَلَ يَجْمَعُ فِيهَا الطَّعَامَ الَّذِي كَانَ فِي الصَّحْفَةِ وَيَقُولُ: غَارَتْ أُمُّكُمْ، ثُمَّ حَبَسَ الْخَادِمَ حَتَّى أُتِيَ بِصَحْفَةٍ مِنْ عِنْدِ الَّتِي هُوَ فِي بَيْتِهَا، فَدَفَعَ الصَّحْفَةَ الصَّحِيحَةَ إِلَى الَّتِي كُسِرَتْ صَحْفَتُهَا، وَأَمْسَكَ الْمَكْسُورَةَ فِي بَيْتِ الَّتِي كَسَرَتْ فِيه
Narrated Anas: While the Prophet (ﷺ) was in the house of one of his wives, one of the mothers of the believers sent a meal in a dish. The wife at whose house the Prophet (ﷺ) was, struck the hand of the servant, causing the dish to fall and break. The Prophet (ﷺ) gathered the broken pieces of the dish and then started collecting on them the food which had been in the dish and said, "Your mother (my wife) felt jealous." Then he detained the servant till a (sound) dish was brought from the wife at whose house he was. He gave the sound dish to the wife whose dish had been broken and kept the broken one at the house where it had been broken.
— Sahih al-Bukhari, Book 67, Hadith 158
The love was mutual; 'Ā'isha was the Prophet's most-loved person. When 'Amr ibn al-'Ās was appointed the leader of the Muslim army in the Expedition of Dhāt as-Salāsil in 8 A.H., he was just one year into Islam. Ibn al-Ās assumed that the Prophet ﷺ had done so out of his love for him. So he asked him about the person that he loved most, and the Prophet said 'Ā'isha:
حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا خَالِدُ بْنُ عَبْدِ اللَّهِ، عَنْ خَالِدٍ، عَنْ أَبِي عُثْمَانَ، أَخْبَرَنِي عَمْرُو بْنُ الْعَاصِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم بَعَثَهُ عَلَى جَيْشِ ذَاتِ السَّلاَسِلِ فَأَتَيْتُهُ فَقُلْتُ أَىُّ النَّاسِ أَحَبُّ إِلَيْكَ قَالَ: عَائِشَةُ. قُلْتُ مِنَ الرِّجَالِ قَالَ: أَبُوهَا. قُلْتُ ثُمَّ مَنْ قَالَ: عُمَرُ. فَعَدَّ رِجَالاً
'Amr b. al-'As reported that Allah's Messenger (ﷺ) sent him in command of the army dispatched to Dhat-as-Salasil. When 'Amr b. al-'As came back to the Prophet (ﷺ) he said: Who amongst people are dearest to you? He said: A'isha. He then said: Who amongst men? He said: Her father, and I said: And who next? He said: Umar. He then enumerated some other men.
— Sahih Muslim, Book 44, Hadith 9
During their marriage, the Prophet ﷺ was always understanding of 'Ā'isha's needs according to her age. She herself narrated such stories. For example, when they first got married, the Prophet ﷺ raced her and she beat him. A few years later, he raced her again and he beat her then joked with her that they were then quit. This is the leader of the Muslim world finding time to race joyfully with his wife while the Romans were poised to attack to bridge the gap between him and his spouse:
عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا أَنَّهَا كَانَتْ مَعَ النَّبِيِّ صلى الله عليه وسلم فِي سَفَرٍ قَالَتْ فَسَابَقْتُهُ فَسَبَقْتُهُ عَلَى رِجْلَىَّ فَلَمَّا حَمَلْتُ اللَّحْمَ سَابَقْتُهُ فَسَبَقَنِي فَقَالَ: هَذِهِ بِتِلْكَ السَّبْقَةِ
Narrated Aisha, Ummul Mu'minin: while she was on a journey along with the Messenger of Allah (ﷺ): I had a race with him (the Prophet) and I outstripped him on my feet. When I became fleshy, (again) I had a race with him (the Prophet) and he outstripped me. He said: "This is for that outstripping."
— Sunan Abi Dawud, Book 15, Hadith 102
It is obvious from the number of hadiths that 'Ā'isha narrated that her knowledge of Islam was quite high. In addition, her worldly knowledge and wisdom way beyond her age may have contributed to the success of the marriage. In Al-Isāba by Ibn Hajar al-'Asqalani, he quoted several opinions of the companions and the following generation about the knowledge and wisdom of 'Ā'isha. Masrūq ibn al-Ajda' said that the elderly among the companions of the Prophet ﷺ used to ask her about the obligations in Islam. 'Atā' ibn Abi Rabāh said she was one of the most knowledge about jurisprudence, and had one of the wisest decisions about worldly matters(*). 'Urwah ibn az-Zubayr said he had not met anyone more knowledgeable about jurisprudence, medicine, or poetry than 'Ā'isha. Abu Mūsa al-Ash'ari said that whenever they had a problem that they could not solve, they would ask 'Ā'isha and she would have knowledge of the matter. Ibn Shihāb az-Zuhri said that if the knowledge 'Ā'isha was compared to the collective knowledge [about Islam] of all the other wives of the Prophet ﷺ or all the other women, her knowledge would outweigh theirs (**).
This does not come as a surprise with 'Ā'isha ranking number four in the list of narrators of hadith (after Abu Huraira, 'Abdullah ibn 'Umar, and Anas ibn Mālik) with 2,210 hadiths. This conveyed to us an almost complete picture of how the Prophet ﷺ behaved at home with his wives for us to take as a role model.
Conclusion. The marriage, in spite of the age difference, was highly successful, compatible, and filled with mutual love. 'Ā'isha always displayed wisdom beyond her age during the marriage, and she conveyed over two thousand hadiths that showed us how the Prophet behaved at home.
While Islam permits marriage of young women when they reach puberty, this does not mean that it is a mandate that all should follow. Parents should consider the compatibility of the bride and the groom, discuss with their daughters the benefits and risks of a proposal, then seek her approval. If there are cases of abuse of child marriage, let that be due to misunderstanding of teachings of Islam or deliberation, said people are to blame; not Islam. The marriage of the Prophet ﷺ and 'Ā'isha was a happy marriage with lots of benefit to both of them, as well as to the entire Muslim nation that followed. What is there to defend?