Thankfully, it seems the torturous 400 days he had spent in an Egyptian prison has failed to dampen the passion, hunger and drive within Greste, which saw him convicted of a crime he did not commit.

The Al Jazeera journalist, who was released from his Egyptian prison "box" seven weeks ago, could have been forgiven for keeping his address light, steering clear of topics that could land him in hot water.

After all, he still stands accused of supporting the banned Muslim Brotherhood, and his colleagues are not yet free pending the outcome of a retrial.

On the one hand he praised the Foreign Minister Julie Bishop, whom he warmly embraced upon her arrival, but he was also unafraid to speak passionately about principles of free speech.

"As everyone here knows, we are not meant to be friends of the government, friends of politicians, we are meant to hold them to account," Greste said, looking in her direction.

"That's our job, it is why we exist, it is the whole point of the fourth pillar, what the fourth estate is supposed to do, and we shouldn't be apologetic about that."

When asked about the topic of asylum seekers, and the lack of access granted to media outlets to information and their conditions, he was steely and direct.

"The public has a right to know, it's as simple as that. We hired the government, they work for us, not the other way around. And ... if we lose sight of that, if we lose sight of the public's need to know and to make decisions and to make democracy work, then again I think we - I think we run the risk of losing control."

Press Club lunches rarely take place on a Thursday, only when a prime minister or opposition leader is invited to the lecturn, and Greste was humbled - if a little frightened - to be speaking to his peers.

"Believe me, this is as scary as anything I went through in prison," he joked, with his infectious beaming smile.

During his warm tribute of Ms Bishop and her team, at the outset of which he asked her to stand for a round of warm applause, he made note of her "laser-like eyes".

"One person, again I can't say who, commented on your uncanny ability to smile very warmly at a particular diplomat and at the same time burn holes through the back of their skulls, giving them the distinct impression that they've just been hugged by the Terminator."

Greste displayed none of what he described as a journalist's reputation of being "a cranky cantankerous lot."

But he remains utterly humbled that the "media somehow abandoned the habits and the instincts of a lifetime to line up behind us in an extraordinary way".

"It was empowering, helped put rods of steel in our spines ... because this was something far bigger than the three of us alone. This was about the universal principles of freedom of expression, of the public's right to know, and we knew that our colleagues were right there with us.

"This matters not just because of the impact on us and our case - right now the very idea of a free press is under attack from groups who take the heads off journalists, to individuals who would shoot up a magazine office in Paris or a free speech conference in Denmark, to governments trying to limit the scope of our work with draconian legislation.

"What you [our journalistic colleagues] did was serve notice on anyone who would attack those most fundamental principles [and show] that we are united. You made it clear that these are things we are prepared to fight for as one, and whatever happens from here, we must not lose that singular voice."

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