An Israeli Foreign Ministry spokesperson said the incident was still under review and had no immediate comment on the pope's words.
In previous guidance from 2016, the Vatican said the ashes must be kept in "sacred places", and therefore neither at home, divided among family members nor scattered to the wind.
The attack was carried out in a university gymnasium in Marawi, a city in the south of the country besieged by Islamist militants for five months in 2017.
"Many hostages have been freed but many are still in Gaza. We think of them, of their families, who had seen a light, a hope of embracing their loved ones again."
Italian rabbis questioned the worth of "decades of Jewish-Christian dialog" if when Jews are attacked the Vatican responds with "diplomatic acrobatics."
The Pope asked for prayers so that both sides would "not go ahead with passions, which in the end, kill everyone".
The Vatican has been vocal in calling for the release of all hostages as well as a ceasefire.
Currently, the official Vatican position is that it neither confirms nor denies possession of Herodian Temple objects such as the golden Menorah, sacred tables, altars, and priestly garments.
The hostages, captured by Hamas on October 7th, 2023, are reported to be in dire conditions, with fears of torture and urgent medical needs.
The pontiff renewed his calls for a ceasefire and for the release of hostages taken by Hamas during its Oct. 7 attack.