ethnicSwede:

Muhammad was a pedophile, even according to the most stringent clinical definition of pedophilia - the DSM-IV-TR:

A. Over a period of at least six months, recurrent, intense sexually arousing fantasies, sexual urges, or behaviors involving sexual activity with a prepubescent child or children (generally age 13 years or younger).

B. The person has acted on these sexual urges, or the sexual urges or fantasies caused marked distress or interpersonal difficulty.

C. The person is at least age 16 years and at least 5 years older than the child or children in Criterion A.

Note: This does not include an individual in late adolescence involved in an ongoing sexual relationship with a 12- or 13-year-old.

PsychiatryOnline - Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition

Muhammad was engaged to Aisha when she was only 6 year old and he was 51, and consummated the marriage while she was still pre-pubescent, aged 9 lunar years old. Thus he fulfilled all three requirements needed for a positive diagnosis.

Zakaria Fadli:

My position is that even if she was actually 9, she can’t be called a child and was biologically and psychologically mature enough for marriage.
Was she a child?
The allegation that she must have been a child comes from a simple glance at her age. A 9-year-old is clearly a child, right? In modern society in 2017, yes. But it’s certainly not true for the past.
No matter what period we are examining, childhood is more than a biological age, but a series of social and cultural events and experiences that make up a child’s life
The time at which these transitions take place varies from one culture to another
What is clear is that we cannot simply transpose our view of childhood directly onto the past.
Over the course of American history, the most commonly observed age of consent was 10 years. In 1880, 37 states had an age of consent of 10 years while 10 states kept an age of consent at 12, and Delaware maintained its age of consent at seven years, having lowered it from 10 in 1871.

Was she prepubescent or biologically immature?
the facts that Western age of consent was as low as 10, just 150 years ago, and that Aisha said a girl becomes a woman at age 9 shows that most girls in those societies were biologically mature enough for marriage at those ages. If you argued against that point, you’d have to argue that you know more today about the biological and sexual maturity of girls hundreds of years ago, than entire Arabian and Western societies knew about their own people.
Mortality, danger, unpredictability and polygyny are all scientifically shown to cause earlier sexual maturation, and these were all much higher in 7th century Arabia than in 18th century Europe under Napoleon. So if European lawmakers 220 years ago concluded that 10 and 11 were the ages when most girls in their society were mature enough for marriage , then it’s practically certain that most girls in Arabia 1400 years ago would have been mature at a far younger age.
"an analysis of cross-cultural data shows that girls undergo puberty significantly earlier in polygynous societies and in nominally monogamous societies with a high incidence of divorce(and thus a higher incidence of serial polygyny)"[1]
[1]Satoshi Kanazawa, Psychology Today, “Why Has the Age of Puberty Declined in Recent Decades? II”

Was she psychologically or mentally immature?
"Human beings are the most cognitively flexible species on the planet and infants and young children are sensitive to early environmental conditions and can alter their path of development, based on current conditions, in anticipation of future conditions"[2]
"Conditional adaptations — children’s brains and bodies tend to respond to dangerous or unpredictable environments by growing up fast and living for the here and now"[3]
If humans are indeed the most cognitively flexible species on the planet, with their brains growing faster in dangerous or unpredictable environments, and the West considered most women in their society psychologically ready for marriage by age 10 and 11, just 150 years ago [2], then it’s practically certain that under the much more dangerous and unpredictable conditions of 7th century Arabia, most girls would have been psychologically prepared for marriage at 9-years-old.
[2]Daniel Nettle, “Flexibility in reproductive timing in human females: integrating ultimate and proximate explanations,” Philosophical Transactions of the Royal Society Biological Sciences, 366, no. 1563 (2011): 357-58,
[3]David Bjorklund, and Anthony Pellegrini, “Evolutionary Perspectives on Social Development,” The Wiley-Blackwell Handbook of Childhood Social Development, ed. Peter Smith and Craig Hart (West Susex: Blackwell Publishing Ltd, 2011), 69-70.

Was Mohammed PBUH a pedophile
The obvious problems with using this label are, as we’ve established in the previous three sections, that Aisha was neither prepubescent, nor a child.

Secondly, there’s no evidence suggesting “fantasies, urges or behaviours” - Of the 12 wives the Prophet PBUH married in his lifetime, only one was even a virgin. His first wife was older than him, and all his others were widows or divorcees. Many of the marriages were demonstrably advantageous in bringing different tribes into Islam. Hardly the profile of a paedophile or sexual deviant.
Lastly, if you persist with the paedophile label, you’re effectively arguing that the entire world suffered from the same psychiatric illness for thousands of years, including your own ancestors, and it only stopped in the 20th century. I hope you can see that’s a ridiculous position to argue for.

Chase Brewer:
dude, I usually like arguing with you. But stop arguing with fools, they know nothing! It's like western civilization doesn't consider you an adult until you're 21. While other countries have children in the military and girls becoming wives as soon as they get their period. Ignore them bro. These people need their hands held though life.