WARNING: Graphic content

An Aucklander is on trial accused of possessing publications promoting acts of terrorism before later buying a hunting knife.

The man, who was a resident at an Auckland mosque at the time of the alleged offences, faces three charges of possessing an objectionable publication relating to the Islamic State of Iraq and the Levant (ISIS).

Known only as Mr S due to an interim suppression order, he is also charged with possessing an offensive weapon and failing to comply with a police search.

This morning in the High Court at Auckland, Crown prosecutor Henry Steele told the jury during his opening address such ISIS material was "designed to both instruct and inspire".

ISIS, also known by its Arabic name Daesh, is a designated terrorist organisation which captured large parts of Iraq and Syria in its quest to establish an Islamic Sate under Sharia law.

As part of its operation, ISIS also attempted to inspire people around world through its success and propaganda to carry out acts of terrorism.

"You no doubt will know of the black flag of ISIS," Steele told the jury.

The material Mr S is accused of possessing - from mid-2018 - is highly graphic in nature and has since been declared objectionable by the Chief Censor for promoting acts of extreme violence, cruelty and terrorism.

Two of the publications include a series of still images with nasheeds (hymns and chants), while the other is a video.

One publication, titled "We came to fill horror everywhere", displays men dressed in black with assault rifles, the ISIS flag and a city on fire. The lyrics include: "We will drink from the blood of disbelievers."

A second, called "What a victory for he who got Shahada", features a person in black with a machine gun and an ISIS flag. Shahada is a reference to martyrdom, while the lyrics are equally as graphic.

Steele said the lyrics advocate for Jihad and terrorist attacks in countries of disbelievers.

He said Mr S also posted some of the lyrics on his personal Facebook account.

The video, described by Steele as a "how to kill non-Muslims", shows a prisoner having their throat and wrists cut and a "non-believer" running with an explosive device strapped to him before it explodes.

Steele told the jury they would watch the video during the course of the trial.

The prosecutor said Mr S is charged with possession of each of those three publications, which were electronically bookmarked online, because viewing the material online was sufficient to amount to possession.

"The law is that way to avoid people simply watching them time and again online, never downloading them and saving them," he explained to the jury.

He said the jurors must decide if Mr S had possession without lawful authority or excuse and whether he had a reasonable cause to believe that publications were objectionable.

Reasonable, Steele explained to the jury, was an objective test by the "person on the street, you".

"What would the reasonable person make of these publications?"

Steele said Mr S, after looking at other ISIS-related material with increasing frequency, then decided to buy a knife and have it couriered to the mosque.

The prosecutor held up the weapon, inside a plastic display, for the court to see.

"As you'll see it's not a small knife, not the sort of knife you'd have in your kitchen drawer," he said.

"It's a knife with a very specific purpose."

The hunting knife is also in a camouflage sheath.

While awaiting the delivery of the knife, Mr S was arrested and his electronic devices seized by police.

Kieran Raftery QC, who is defending Mr S, told the jury in a brief opening statement his client accepted he had listened to the nasheeds and bought the knife.

However, he disputed Mr S was in possession of the knife in a public place and said the man may have had lawful authority to view the video, which was only watched once.

"How was he to know what was in it until he viewed it?"

He said possession of the video was disputed and the defence's case would become clearer as the trial progressed.

"Mr S doesn't have to prove his innocence," Raftery added.

The trial continues.