Mohammed Bouyeri stunned the courtroom when, in the final minutes of his two-day trial he declared: "If I were released and would have the chance to do it again ... I would do exactly the same thing."
"What moved me to do what I did was purely my faith. ... I was motivated by the law that commands me to cut off the head of anyone who insults Allah and his prophet," he said.
Bouyeri, 27, faces life imprisonment in the Nov. 2 killing of Van Gogh, who was shot, stabbed and nearly beheaded on an Amsterdam street. A verdict is to be handed down this month.
Bouyeri glanced at notes, paused between sentences and chose his words carefully. Some spectators rose to their feet as he spoke, visibly stunned by his comments.
At one point, he addressed the victim's mother, Anneke, who was sitting in the public gallery. "I have to admit I don't have any sympathy for you," he said. "I can't feel for you because I think you're a nonbeliever."
The killing is believed to have been an act of retribution for Van Gogh's film "Submission," which criticized the treatment of women under Islam.
The killer left a five-page note fixed to the filmmaker's body with a knife. Along with religious ramblings, the note threatened Dutch politician Ayaan Hirsi Ali, who wrote the screenplay for Van Gogh's film, and others he perceived as enemies of fundamentalist Islam.
Lead prosecutor Frits van Straelen told the court Bouyeri would kill again unless he is locked up for life.
"The accused preaches a message of hate and violence," Van Straelen said. "He preaches that anyone who thinks differently can be killed ... He is and remains a danger to our society."
"The attacks in London last week make it clear that the problem of Islam-oriented terrorism continues, but I hope that the result from this case can help peace return," the prosecutor said.
The killing of Van Gogh, a distant relative of the painter Vincent van Gogh, led to a wave of retaliatory attacks on mosques in a country once renowned for its tolerance.
It also led to an intense national debate over the integration of Muslims, who make up 6 percent of the Netherlands' 16 million people.
Bouyeri was born in Amsterdam to Moroccan parents, and became increasingly radical in his beliefs in the two years leading up to the murder, according to prosecutors.
His statement in court Tuesday was his first public comment since he was arrested in a shootout with police after the slaying. Bouyeri had not mounted a defense during the trial and ordered his lawyer not to speak.
Bouyeri, allegedly a member of a terrorist cell known as the Hofstad Network, is said to have attended private prayer sessions with a Syrian spiritual leader, Redouan al-Issar, who disappeared shortly before the Van Gogh killing.
Twelve other suspected group members are awaiting trial on separate terrorism charges.
Bouyeri is also accused of threatening politicians, impeding democracy, illegal weapons possession and manslaughter for attacks on police and bystanders.
Bouyeri was arrested by police after a shootout while holding the gun prosecutors say was used in the murder. Prosecutors say he is also tied to the crime by witnesses, blood spatters, ballistic evidence, a photo and DNA analysis.
On Tuesday, Bouyeri addressed the police officers he is accused of firing on eight months ago, saying: "I shot to kill and to be killed. You cannot understand"
Van Straelen said Bouyeri must have had financial help, but there were no other suspects in the case.
"This shows how dangerous religious obsession is," Theodor Holman, who was a friend of Van Gogh's, said outside the courtroom. "All you have to do is insult Islam and (Bouyeri) feels it justifies brutally slaughtering you."