The Hadith are indeed secondary to the Qur'an, but the Qur'an says nothing about Aisha's age at the time the marriage was consummated.
In "Truth about the Prophet's wife" (September 28 to October 4), Myriam Francois-Cerrah worries that Muhammad is being maligned by critics who "allege that Aisha was just six years old when she was betrothed" to him and their marriage was consummated when Aisha was nine. She omits, however, to mention that this information comes exclusively from Muslim sources.
The Hadith are indeed secondary to the Qur'an, but the Qur'an says nothing about Aisha's age at the time the marriage was consummated. There are, on the other hand, numerous Hadith to the effect that she was indeed nine years of age at that time. Sahih al-Bukhari, regarded by Muslims as being the most authoritative, mentions this fact five times (5:58:234, 5:58:236, 7:62:64, 7:62:65, 7:62:88) and it is mentioned a further five times in Sahih Muslim (8:3309, 8:3310, 8:3311, 41:4915, 41:4917).
The 9th-century Persian scholar Ibn Tabari differed: he believed she was 10.
Francois-Cerrah's claim that Aisha must have been older because of a Qur'anic verse about marriage being void unless entered into by two consenting adults – repeated twice just to reassure herself – is mere wishful thinking.
The Qur'an also forbids a Muslim man from taking more than four wives, but this verse did not of course apply to Muhammad himself, who had 11 to 13 wives in total.
But according to the only sources available, he did have a child bride. And the Hadith may not all be reliable, but the fact that one does not like a Hadith (or many Hadiths, in this case) does not alter its veracity one bit.
Muslims are enjoined to follow the example of their prophet, so Muhammad's marriage to Aisha is indeed still used to justify child marriage today and not just by the governments of Iran and Saudi Arabia. – Alex Myers, Cape Town