The Islamic College of Brisbane on Sunday opened its doors to people of all faiths and non-believers to grieve for the men, women and children gunned down at two mosques on Friday.

Hundreds who could not fit inside spilled out onto the pavement and watched the service as it was streamed live on Facebook, while small groups broke away for prayer and loved ones consoled each other.

"This act of terror has not only affected Muslims, but all human beings, believers and non-believers alike, across the world, and together we will bear the burden of grief," Islamic Council of Queensland president Habib Jamal told the crowd.

"Loss of a single life is sad and today the sadness has been multiplied 50 times, and could possibly go higher.

"We hope that it does not."

Mr Jamal told of his neighbours living in constant fear for their safety, women whose hijabs had been ripped off by strangers, Muslims spat on, abused on public transport and assaulted.

He reflected on comments made in the "corridors and chambers of power" that Islam was a disease, the mocking of religious attire and calls for a "final solution" towards Muslim immigration.

"We need our leaders to lead the way, and not rely on divisive politics to guide votes," he added.

"We need to work towards creating a society where we all belong, one in which we see beyond our differences and recognise our common humanity."

Imam Uzair Akbar, Queensland Council of Imams president, said there'd been an endless stream of visitors at the Holland Park Mosque since the attack.

They have left flowers and notes, painted signs and spoken of their support.

"(But) we've got a lot of work to do," he told the crowd.

"The day this incident occurred, one of my Imam friends, he was in the shopping centre, and somebody came to him and said that he should have been in New Zealand.

"So that sentiment is out there, and if we do not address this right now and completely eradicate and uproot it, God forbid something similar to Christchurch may take place in Australia."

A roar of cheers and clapping broke out when Premier Annastacia Palaszczuk told the crowd Queensland was proud of its multicultural and multifaith community.

"We gather today, friends, in sorrow, but we gather and stand united," she said.

"We will not give in to the hatred that was behind this atrocity."

Their remarks came after police charged a 23-year-old Browns Plains man after he allegedly rammed his car into the gates of the Baitul Masroor Mosque on Saturday.

He is accused of shouting offensive words at people inside before driving home and later being arrested.

Australian Associated Press