Rabbi Eli Schlanger and Rabbi Yaakov Levitan will be buried shortly after services on Wednesday.
The religious leaders were among 15 killed when Sajid Akram, 50, and his son Naveed, 24, fired at scores of people at Sydney's Bondi Beach on Sunday night as they celebrated the Jewish festival of lights.
Rabbi Schlanger's funeral will be held at Chabad of Bondi, just a kilometre away from the terrorist attack, while Rabbi Levitan's service will take place at Macquarie Park in Sydney's north.
Jews are traditionally buried within 24 hours from time of death but coronial investigations has meant funerals are being held later.
Rabbi Levitan has been remembered as a devoted husband and father.
Similarly, Rabbi Schlanger - who helped organise the Hanukkah event targeted by the gunmen - left behind a wife and five young children, including a two-month-old baby.
Counter-terrorism investigators are poring over swathes of seized material as they try to uncover how father-and-son shooters committed the atrocity.
The premeditated actions were "a barbaric attack against Jewish Australians", Australian Federal Police Commissioner Krissy Barrett said.
"It appears the alleged killers were interested only in a quest for a death tally," she told reporters.
The top cop said early indications pointed to a terrorist attack inspired by Islamic State.
There was no evidence to suggest other people were involved in the attack but she cautioned it was an initial assessment and subject to change.
The NSW joint counter-terrorism team continued to review material seized during search warrants, she said.
Police shot dead the 50-year-old, while his son remains in hospital in a critical condition under police guard.
There are 22 injured patients in Sydney hospitals, three in a critical condition, five in a critical but stable condition and the further patients in stable conditions.
NSW Police Commissioner Mal Lanyon said officers found two home-made Islamic State flags in a car, registered to Naveed, where they also defused two improvised explosive devices.
He confirmed the pair had travelled to the Philippines but noted the reasons for the trip were still being investigated.
"We continue to work through the motive of this tragedy, and we'll continue to do so. It's really important that our investigators continue to be given time to do that," Mr Lanyon said.
"This is a very complex investigation."
Prime Minister Anthony Albanese refused to give further details when pressed on intelligence sharing from Manila.
Mr Lanyon was challenged about why Sajid Akram was granted a permit allowing him to carry six long firearms four years after his son came to the attention of ASIO for affiliating with a radical Islamist preacher in Sydney.
Nearly 260,000 gun licences have been issued across the state, according to latest official figures.
Premier Chris Minns stepped in to defend the police force, saying sufficient resources were devoted to end the shootings.
"(The police officers) engaged the gunmen on a foot bridge with handguns, the offenders had long-range rifles," Mr Minns told reporters.
"There are two police in critical care ... they weren't shot in the back as they were running away - they were shot in the front."
He signalled parliament would be recalled before Christmas to pass tougher gun laws as he urged NSW residents to continue donating more blood to victims.
Mr Albanese said national laws would be strengthened to limit the number of guns per person and citizenship requirements in owning them.
Authorities have ramped up security around Jewish sites, as well as Adelaide Oval before Wednesday's Test cricket match.
Among the 15 Bondi victims were a 10-year-old girl, an 87-year-old Holocaust survivor, a retired police officer and a father who ran at the gunmen, hurling a brick.
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