During those time marrying young girl was common. However the great Prophet marriage to Aisha was due to religious and political purposes. Even if she was 10yrs old and so long she reached state of puberty, its acceptable.
Anyway contrary to popular myth, A’isha was not six years old when she married Muhammad. All of the historical evidence when examined as a whole suggests that
A’isha was born 4 years before Muhammad began his prophetic mission and was married to the Prophet on her father’s initiative in the tenth year of Muhammad’s mission (620) – she was therefore around 14 years of age at the time of betrothal (620 AD) and 16-18 years old at the date of marriage (624 AD) and this was a normal marriage age until quite recently (all the evidence is analyzed in this peer rev
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