Mohammad: Sex with 9 year old
The tactics section consists of quick examples of a specific technique that can be employed during the course of a debate or discussion to help give you an advantage.
Tactic: Argue for the most defensible claim that is fundamentally devastating to your opponent's position
For example: An atheist who argues 'Mohammad was the worst person who ever existed and nothing he said was ever worthy of consideration', will be far less effective than a person who goes out of his way to be conciliatory.
If he had instead argued something like, 'in light of Mohammad's consummating his marriage with a 9 year old girl, the moral example of the life Mohammad lead could be improved upon for today', the claim that is being made is far more narrow, far more focused, and requires far less to defend.
Takeaway: most Muslims would take serious issue with either statement, so choose the statement that's easier to attack and defend.
In Islam, Mohammad’s life is the best example of how to lead a virtuous life and how he lived is to be emulated by all faithful Muslims.
It is blasphemous to suggest that Mohammad’s moral example could be improved upon.
Mohammad's marrying a 6 year old girl and consummating the marriage with her when she was 9 years old means that Mohammad's example of how to lead a moral life could be improved upon.
It has passages like the following (the link is to the specific quote in the USC-MSA Compendium of Muslim Texts):
Volume 7, Book 62, Number 88: Narrated ‘Ursa:
The Prophet wrote the (marriage contract) with ‘Aisha while she was six years old and consummated his marriage with her while she was nine years old and she remained with him for nine years (i.e. till his death).
The Prophet is, of course, Mohammad, who is seen consummating a marriage with a nine year old.
I ask in my "Why Engage in Religious Debates?" essay: "If people honestly believed that this kind of behavior is the highest morality that we could even aim for, what effect could this kind of thinking have in the real world today?"
The usual response to this claim varies from "that was a different time, and you're judging Mohammad by today's standards" to "how dare you even attempt to criticize the prophet?"
The simplest response is to remain as narrow and focused on the specific claim as possible: "I'm not condemning Mohammad for his actions in this case. I'm merely saying that today people shouldn't follow his example because it's far from the most moral way to act."
Stick on the point that a grown man having sex with a 9 year old is not an acceptable situation. Therefore, it is not moral to follow Mohammad's example today.
This argument is most effective in a public setting because the situation ends with the Muslim either publicly defending having sex with a 9 year old as the epitome of moral action (not just 'forgivable' but an example of the highest moral life) -- or publicly stating that Mohammad's example needs some polishing to be applicable for today.