Sultan Hassanal Bolkiah said authorities had been considering the new Sharia Penal Code for years and it will be enforced in 'phases'.
Punishments under the Hudud code may include stoning for adultery, amputation for theft and flogging for drinking alcohol or even having an abortion.
The code will make Brunei the first ASEAN country to enforce a national Sharia law.
Speaker: Dr Ahmad Farouk Musa, director of the Islamic Renaissance Front in Kuala Lumpur
FAROUK: I've heard about this issue a few years ago, I mean they've been talking about it. They say they wanted to implement Shariah and I've read on Facebook postings like some Malaysians basically they agreed to the proposal made by the Sultan and they even wanted to migrate to Brunei, some of them.
LAM: Why do you think the Brunei Royal Family has decided on this move to Shariah laws. Has the family always been so religious?
FAROUK: No, well, I guess this is the paradox. I think most of us, we have been reading news about the Sultan and his family. Well, I'm not going to comment about the Sultan himself, but I guess that people know about the lifestyle of his family members.
LAM: Indeed, Brunei as a country and the people of Brunei as far as I can understand, they've always been fairly laid-back and it's a predominantly Malay culture, isn't it?
FAROUK: Yes, yes, it is a predominantly Malay culture and I guess that the reason why the Sultan is very insistent in trying to implement Hudud and Shariah is basically because of political reasons. I guess it would cement his authority over his citizens and it will give him the power, like, my decree is basically a decree by God and I'm actually voice of God on earth or something like that.
LAM: So in other words, to have God on his side?
LAM: But Brunei's Royal Family has always had a firm grip on power in the nation. Why the sudden change now, do you think?
FAROUK: I guess it has something to do with the current climate in the Islamic world. We are all aware of this Arab Spring, like they had deposed many of their leaders and dictators and even the Saudi government is under threat. There have been a lot of pro-democracy movements in Saudi Arabia and we have heard of Hamza Kashgari who Tweeted and he wanted to get asylum in New Zealand and on his way, there was a transit in KL and he was deported back to Saudi Arabia and like nobody knows where is he right now.
LAM: Just very briefly Dr Ahmad Farouk, will this take Brunei down the Saudi road, do you think, with more capital punishments and erosion of personal freedoms and indeed, women's rights?
FAROUK: Obviously. I mean this what is going to happen to Brunei, and we have heard about the Saudi Shariah law, about Hudud about how this one lady, maid, who was being beheaded because she thwarted an attempt by her employer to rape her and inadvertently killed her employer and then she was beheaded. But then a Saudi cleric recently raped and kill his five old year daughter and he was just initially released but then later, on retrial, and he was he was put in jail for a few years and I guess that's a gross injustice.