Hamdi Alqudsi, 42, was found guilty of violating Australia's foreign incursion laws for making travel arrangements for a group of would-be jihadists in 2013.
Giving evidence for the first time at a sentence hearing, he expressed regret and said that he loved Australia.
Alqudsi also claimed he thought that IS would help civilians.
He faces a maximum 10 years in jail for seven counts of providing services with the intention of supporting hostile acts.
"As an Australian I should have minded my own business," Alqudsi told the New South Wales Supreme Court.
"I love Australia, I always have."
On Wednesday, Alqudsi admitted for the first time that he knew the seven men he assisted in 2013 planned to take up arms against Syrian government forces.
He said he should have limited his involvement to taking donations for Syrian civilians trough registered charity groups.
Alqudsi broke down in tears while giving evidence, saying he now realises he was breaking the law.
"At the time, I felt it was the right thing to do," he said.
"I am really, really sorry for what I have done."
Two of the seven men Alqudsi helped were killed in Syria. Two others have returned to Australia, another was arrested before he could leave the country, and the fate of two other men is unknown.
Alqudsi said his first impression of the Islamic State group was that they were a force for good.
The prosecutor put it to him that it was obvious the men intended to travel to Syria to fight.
"You knew these men were going to be out in the fields of Syria engaging in warfare," David Staehli SC said.
"Yes, I did," Alqudsi replied.

Australia had a first-innings lead of 155 runs after bowling their hosts out for 105 in Pune.
The tourists scored 285 in the second innings, setting India a record target of 441 to win.
However, India were all out for 107 as they lost inside three days, with left-arm spinner Steve O'Keefe taking 6-35.
On a turning pitch, O'Keefe also took 6-35 in the first innings, while fellow spinner Nathan Lyon snared five wickets in total - with figures of 4-53 in the second innings - as Australia's spin duo outperformed their Indian counterparts.
Visiting captain Steve Smith also played a key part in the victory as he scored 109 in the second innings, his maiden Test century in India.
The win was Australia's first in India since 2004.
"I'm really proud of how boys have performed," said Smith. "O'Keefe was absolutely outstanding in the match."
India captain Virat Kohli was critical of his team, describing it as their "worst batting display in two years".
"We got outplayed in this match. We have to take it on the chin," he added.
"We never took them for granted but we were never good enough during the three days."
India, the top-ranked Test team, have not lost a home Test series since 2012 and the second match starts in Bangalore on Saturday, 4 March.
A Sydney man who helped seven young men travel from Australia to Syria to join the Islamic State conflict has told a court he is "not a terrorist".
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India's 19-Test unbeaten run was emphatically ended as Australia beat them by 333 runs in the first of a four-match series.