Sonny Bill Williams and the dispensation to wear a special Blues jersey without the BNZ and Investec logos.

Is there a parallel with the great Michael Jones, a man who because of his christian beliefs chose not to play for the All Blacks on a Sunday?

What do you think? Where are you positioned on this.

It's such a polarising issue. Williams has copped a lot of criticism for this. Some have called him a hypocrite - for example, he plays at Westpac trust stadium in Wellington. He plays in front of the ASB stand at Eden park.

So what's the difference? Why won't he wear the BNZ's logo on his Super Rugby jersey?

Well I don't know the answer to that, but I suspect Williams objects to wearing the brands of banks and investment houses on his person. That is the difference. By wearing BNZ on his collar he perhaps sees that as a direct and personal endorsement, and that doesn't sit with his Islamic beliefs.

In Sharia law, you can't use money to make money. If you're going to make money, it has to be from a legitimate trade. So if you buy a house that's worth half a million dollars, the Sharia bank gives you whatever you need on top of your deposit, but values the property at, say, $750,000. And you don't pay interest - you essentially pay rent to the bank. So you pay back what the bank gave you, plus the extra $250,000. And you can pay it off in full at any time without penalty.

The British banks have been offering Sharia mortgages for over 15 years. It's probably something our banks should explore too, if they haven't already. There's clearly a market for it.

But the problem Sonny Bill Williams runs into, particularly in a country that is wary of Islam, is where does the interpretation of Sharia law start and stop with him.

In some countries, sharia law is carried out to the extreme. Saudi Arabia is one example. Women can't drive car, or speak alone to a man who is not her husband or relative. A woman who has been raped can't testify in court against her rapist. A man can divorce his wife. A woman needs her husband's consent to the do the same. Theft can be punishable by amputation. Adultery or illicit sex is punishable by stoning to death.

It's a given Williams' interpretation of the law isn't the extreme version. I'm pretty sure his wife will drive their children to Plunket in a car. And you get the impression, given some of the work Williams has carried out in a humanitarian and charity capacity, that he is something of a 'soft soul'.

But he does open himself up to judgement and criticism.

The question is, does this set a precedent? No. I don't think it is. Williams is a rarity in New Zealand. A Muslim elite athlete.

If he chooses not to endorse banks, alcohol companies, tobaccos companies or gambling houses, then that's his decision and if his employers aren't comfortable with that, they don't have to contract him. Personally, I'm okay with it.

That Sonny Bill Williams has strong beliefs and he follows through with those beliefs in both a personal and professional capacity, well, I take my hat off to him.

He stands up for what he believes in. And that, on some level, surely is an admirable trait.