Brunei is introducing strict new Islamic laws that make anal sex and adultery offences punishable by stoning to death.
The new measures, that come into force on Wednesday, also cover a range of other crimes including punishment for theft by amputation.
The move has sparked international condemnation.
Brunei's gay community has expressed shock and fear at the "medieval punishments".
"You wake up and realise that your neighbours, your family or even that nice old lady that sells prawn fritters by the side of the road doesn't think you're human, or is okay with stoning," one Bruneian gay man, who did not want to be identified, told the BBC.
The sultan of the small South-East Asian nation on Wednesday called for "stronger" Islamic teachings.
"I want to see Islamic teachings in this country grow stronger," Sultan Hassanal Bolkiah said in a public address, according to AFP news agency, without mentioning the new laws.
Homosexuality was already illegal in Brunei and punishable by up to 10 years in prison.
Muslims make up about two-thirds of the country's population of 420,000. Brunei has retained the death penalty but has not carried out an execution since 1957.
The law mostly applies to Muslims, including children who have reached puberty, though some aspects will apply to non-Muslims.
Under the new laws, individuals accused of certain acts will be convicted if they confess or if there were witnesses present.
Individuals who have not reached puberty but are convicted of certain offences may be instead subjected to whipping.