Some Muslims are fond of condemning western morality – alcoholism, nudity, premarital sex and homosexuality often being cited as examples. But Muslims do not have a monopoly on morality. In the west, child marriages and sex with children are illegal. Unfortunately, the same cannot be said for many Muslim countries.

I recently saw the documentary on the Dancing Boys of Afghanistan. It exposed an ancient custom called "bacha bazi" (boy for play), where rich men buy boys as young as 11 from impoverished families for sexual slavery. The boys are dressed in women's clothes and made to dance and sing at parties, before being carted away by the men for sex. Owning boys is considered a symbol of status and one former warlord boasted of having up to 3,000 boys over a 20-year period, even though he was married, with two sons. The involvement of the police and inaction of the government means this form of child prostitution is widespread.

The moral hypocrisy is outrageous in a country where homosexuality is not only strictly forbidden but savagely punished, even between two consenting adults. However, men who sodomise young boys are not considered homosexuals or paedophiles. The love of young boys is not a phenomenon restricted to Afghanistan; homosexual pederasty is common in neighbouring Pakistan, too. In my view, repression of sexuality and extreme gender apartheid is to blame.

And in the Middle East, it's young girls who are considered desirable and men are able to satisfy their lusts legally through child marriages. In Yemen, more than a quarter of girls are married before the age of 15. Cases of girls dying during childbirth are not unusual, and recently, one 12-year-old child bride even died from internal bleeding following sexual intercourse. In another case, a 12-year-old girl was married to an 80-year-old man in Saudi Arabia.

So why is the practice of child marriage sanctioned in Muslim countries? Unfortunately, ultra-conservative religious authorities justify this old tribal custom by citing the prophet Muhammad's marriage to Aisha. They allege Aisha was nine years old when the prophet married her. But they focus conveniently on selected Islamic texts to support their opinions, while ignoring vast number of other texts and historical information, which suggests Aisha was much older, putting her age of marriage at 19. Child marriage is against Islam as the Qur'an is clear that intellectual maturity is the basis for deciding age of marriage, and not puberty, as suggested by these clerics.

Whatever one's view on the prophet's marriage, no faith can claim moral superiority since child marriages have been practised in various cultures and societies across the world at one time or another. In modern times, though, marrying children is no longer acceptable and no excuse should be used to justify this.

I find the false adherence to Islamic principles and the "holier than thou" attitude of some Muslim societies similar to the blatant hypocrisy and double standards of 19th-century Victorian Britain, where the outward appearance of dignity and prudishness camouflaged an extreme prevalence of sexual and moral depravity behind closed doors. In those days, too, there were many men willing to pay to have sex with children – until a plethora of social movements arose that resulted in changes in laws and attitudes in society.

A similar shift in social attitudes is also required in traditional Muslim societies. Having boy sex slaves or child brides should not be seen as badges of honour. Instead, Muslims need to do more to attach shame to such practices; otherwise, acceptance of this behaviour will make them complicit in the sexual exploitation of children. I fail to understand why Muslims are so vocal on abuses by the west in Abu Ghraib, Guantánamo, Iraq and Afghanistan, but display moral blindness when it comes to children? It's about time this silence was broken, so these violations of innocence can be stopped.

A too-passive attitude in dealing with child abuse has rubbed off on Muslim communities in Britain, too. I have heard many stories at first hand of child sexual abuse and rape, which show that the issue is not being addressed at all. Those who have had the courage to speak out have been met with reactions of denial and shame. Such attitudes mean that children will continue to suffer in silence. Sexual abuse of children happens in all communities, as has been revealed by the recent Catholic church scandal. At least, they have finally started to take action. Muslim communities should learn from this and also start being more open, instead of continuing to sweeping the issue under the carpet.

I am finding that more and more Muslims feel it is their duty to criticise others for actions they consider sinful – quoting the following popular saying of Muhammad to justify their interference:

"If you see something wrong, you should correct it with your hand and if you are unable to, then speak out against it and if you cannot do that, then feel that it is wrong in your heart."

I wonder how, then, Muslims can remain silent when it comes to the sexual abuse of children?