While Nawarajan was being searched, police found a hard drive containing videos, magazines and documents widely classified as propaganda, many containing graphic violence.
On the drive was also a typed letter "which tends to promote or support acts of torture or the infliction of extreme violence or cruelty", court documents said.
The man was charged with possessing objectionable material and his sentencing before Auckland District Court today was the second of its kind by only a couple of hours.
Imran Patel, 26, was jailed for three years nine months for similar offending this afternoon.
Judge Collins told Nawarjan he should be "extraordinarily grateful" to his brother who had agreed to put up his place in Wellington as a home detention address.
"The support has come at a significant personal sacrifice," he said.
The pair were ordered to travel directly to the property on the bus tonight.
The horrifying nature of the videos Nawarajan was found with was detailed in a summary of facts.
All contained "graphic scenes of war violence".
A video entitled Massacre of the Shias was essentially 22 minutes of executions.
One scene highlighted as particularly graphic depicted a man allowed to kneel on top of a hill to pray before being shot twice in the back of the head.
"The camera closes in on his face as he lies dying and focuses on the blood spurting out from his cheek," court documents said.
Nawarajan also had 12 electronic issues of Dabiq magazine, a "glossy" Isis-produced publication, one edition of which was found to contain several photos of a Jordanian pilot being burned alive and shots of his charred remains.
The 27-year-old was also sentenced for some "bizarre" acts in Christchurch from November when he scaled a fence in Lyttelton and wandered around the port.
When stopped he told security he was looking for his cat.
Police found Nawarajan under a blanket that night.
He was uncooperative and had to be restrained.
Officers discovered he had two fold-out knives on him and a 30cm hatchet in his backpack, which the defendant said was for "clearing trails".
Judge Collins ordered the man to complete post detention conditions designed to address his alcohol and drug problems which were "at the heart" of his offending.