The High Court hasn't yet granted the pedophile permission to appeal his five convictions for sexually abusing two choirboys at Melbourne's St Patrick's Cathedral in 1996.

Instead, after two days of arguments in Canberra, the judges reserved their decision and requested more written submissions from Pell's barrister Bret Walker SC and Victoria's top prosecutor.

Pell was convicted by a jury in 2018 on the word of a single choirboy that he was sexually abused as a teenager by Australia's highest-ranking Catholic.

Now a man in his 30s, he also has to wait to know if the conviction will be upheld by Australia's seven most senior judges.

Pell is one year into a six-year jail sentence.

Director of Public Prosecutions Kerri Judd QC on Thursday took the judges through 10 points on why they shouldn't quash Pell's convictions and free him from prison, as Mr Walker had argued for on Wednesday.

She urged them to not consider the evidence in isolation, but to look at each piece in combination with the rest.

The judges had pointed to evidence by Pell's master of ceremonies Monsignor Charles Portelli, who claimed at one stage to remember being with Pell on the steps of the cathedral at the time of the offending.

But Ms Judd said he was only able to say that was his practice, and there was evidence the practice was not always followed.

"Quite a number of choirboys and others do say there were occasions when ... he did not stand on the steps but he actually (joined the procession). The choirboys recall having to wait for him to go through," Ms Judd said.

The pair had snuck into the priest's sacristy after Sunday Mass and were caught by Pell swigging sacramental wine before the abuse, the jury accepted.

Ms Judd said the complainant had accurately described the priest's sacristy - a room which ordinarily would not have been used by Pell except that the Archbishop's sacristy was being renovated.

The room was off limits for choirboys.

"If he was going to make this up, if he was fantasising, the place to pick was the Archbishop's sacristy, not a place that Pell would not normally be in," Ms Judd said.

"He's describing this room in great detail," she added, urging judges to look at photos which showed the parts of the room described are not visible from outside.

Mr Walker accused Ms Judd of changing the prosecution's case during the appeal when it came to the five or six-minute window of time when the offending was said to have taken place.

Ms Judd was on Thursday unable to pinpoint when the window of time was said to have begun or what others were doing in that time, which Mr Walker called an "improvised and rickety construction of a Crown case to make something fit that will not fit".

The High Court could now take a number of paths including refusing special leave and ending Pell's appeal hopes.

If leave is granted the appeal could be refused, or it could be granted resulting in the convictions being quashed and Pell being released.

Justice Geoffrey Nettle also hinted that a re-hearing of the original appeal either by the High Court or by sending it back to Victoria's Court of Appeal was an option.

Australian Associated Press