He is one of the most dangerous men in Pakistan and is supposed to be in police detention.
Instead, as several thousand hardline Muslim worshippers knelt in prayer at the Red Mosque in the heart of Islamabad, the voice of Maulana Abdul Aziz called out over them defiantly.
Seven years ago, the radical cleric led heavily armed Al Qaeda gunmen in a bloody siege at the mosque against government forces, which left more than 100 children, soldiers and militants dead.
The brutal denouement, including the killing of his brother and son, set off a wave of Taliban suicide bombings which struck at the heart of Pakistan's military establishment.
Now Pakistan's intelligence services believe Aziz is building a new militia, grabbing land for more madrassas and preparing for another tilt at forcing the country to adopt strict Islamic law. Eyewitnesses said they had seen 30 to 40 heavily armed men from the militant group Sipah-e-Sahaba inside the mosque.
Once again, he is a reminder that one of the West's most important allies against the forces of terror has a problem dealing with the militant voices in the middle of its own capital. In December, a Pakistani court issued an arrest warrant for Aziz but the police have been unable to enforce it. "We are trying our best to implement it," a police official said.
In an interview, Aziz cut a serene figure in a light brown robe, white turban and scholarly spectacles, but offered no comfort to Pakistan's government and those who regard him as the spiritual voice of the country's most deadly terrorists. He described the massacre of staff at the French satirical magazine Charlie Hebdo as the "correct" application of Islamic law for their "blasphemous"
cartoons of the Prophet Mohammed. "Whoever disrespects our Prophet, the sentence is death", he said.
Aziz, whose wife has sworn allegiance to the Islamic State of Iraq and the Levant (Isil), has close links to Ayman al-Zawahiri, now the head of Al Qaeda, and the Afghan Taliban, who he represented in talks with Pakistan's government last year. Students at the madrassa run by his wife in the Red Mosque complex do their work in the recently renamed Osama bin Laden Library.
He repeated his assertion that, while the "brutal murder of young children" at Peshawar's Army Public School "cannot be justified", the killers were responding to offensives by the army in Pakistan's tribal areas.
His words are familiar to regulars at Friday prayers, held in a leafy neighbourhood of Islamabad.
The only solution for Pakistan's problems, he continued, was for its government to adopt hardline sharia, including a ban on music and women appearing in public without covering their faces. And he gave a chilling warning. Unless the government implements his vision of Islamic law soon, he and his followers "will solve it".
Pakistan's intelligence services believe he is in control of an armed militia. In a report seen by The Daily Telegraph, a senior Inter-Services Intelligence official said: "It's evident that he is following an agenda of reviving [the] Lal Masjid mafia in the heart of the federal capital.
"His links with the TTP [Tehreek-e-Taliban Pakistan] and land grabbers pose a security threat to law and order." He added that Aziz had organised a militant wing, the Ghazi Force, operating under two Taliban leaders in the tribal areas.
Aziz has no regrets over the carnage at his mosque in 2007 and continues to deny that there were gunmen in the complex, despite photographic evidence of militants firing machine guns from the roof and the 18 bodies of armed men, including Chechens, Egyptians and Afghans, that were later found by the security services.
The siege followed a violent campaign by female students from the madrassah armed with sticks who patrolled the nearby streets in black burkas, kidnapped an alleged prostitute, harassed Chinese massage parlour staff and eventually torched a government ministry building. At one point they attacked paramilitary troops and seized their weapons and radio equipment.
Aziz said he would not rule out sending the madrassah girls on to the streets and into confrontation with the authorities again. "That might happen," he said.
His defiance challenges the government's repeated vows to fight terrorism in the wake of the Peshawar school attack. Since the killings in December, more than 8,000 people have been arrested and a number of terrorists executed.
The government has begun verifying all mobile phone sim cards in the country - more than 100 million - to thwart communications. However, arresting Aziz, despite his growing influence, deadly history and command over armed fighters, seems a step too far while the battle rages in the border areas.
"While this is going on what we don't want is to open a third front. We can pick this idiot up any time we want to but we don't want to pick on him now and his people start suicide bombings," said a government official.
The government's biggest mistake was to allow the mosque to be rebuilt and Aziz to preach there, he conceded.
"But people thought they were doing a good job, a religious thing, and were guaranteed a place in heaven," he said.