Sunan an-Nasa'i, Volume 4, Book 26, Hadith 3259 (DarusSalam) ⓘ

It was narrated that Abu 'Ubaidah said: "Aishah said: 'The Messenger of Allah married me when I was nine and I lived with him for nine years.'"

أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا عَبْثَرٌ، عَنْ مُطَرِّفٍ، عَنْ أَبِي إِسْحَاقَ، عَنْ أَبِي عُبَيْدَةَ، قَالَ قَالَتْ عَائِشَةُ تَزَوَّجَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم لِتِسْعِ سِنِينَ وَصَحِبْتُهُ تِسْعًا ‏.‏

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Key Source: Marriage to Aisha

Maybe one of the most controversial areas of Muhammed's life was his marriage to a child bride, Aisha. According to Muslim sources, Muhammad married her in his 50s, while she was 6 years old, and the marriage was consummated when she was 9 years old. This relationship in particular is seen...

Key Sources

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also referenced under: Hadith 3257 (Reference) & Book 26, Hadith 62 (In-Book)