The defendants face 32 different charges for crimes against children, such as raping them, making them take part in witchcraft classes, making them try to commune with demons, and more.
The ultra-Orthodox Jewish principal was found guilty of abusing two sisters.
Religious services are being provided through Reaching Out, one of several organizations operated by people affiliated with the Chabad-Lubavitch movement to serve those who are incarcerated.
The billboard was put up on the Almirante Reis avenue - one of Lisbon's longest and busiest streets - and reads: "4,800+ children abused by the Catholic Church in Portugal."
The Vatican said about 330,000 young people have registered for an event in Portugal dubbed "the Catholic Woodstock."
The story first broke on Friday when the Sun tabloid reported a leading BBC presenter had paid a young person 35,000 pounds ($45,000) for explicit photos over three years.
If a young child today suffers abuse, chances are, it will have been recorded in some way. A reconstruction of that moment with the use of modern technology, enables them to speak up.
The initiative falls under the auspices of the Israel Police's Unit 105, a section of the Lahav 433 unit that specifically handles children's safety on the Internet.
The research was a joint effort between scientists at Israel's Hebrew University of Jerusalem and Stanford University in California.
28-year-old Patriot Front member Jared Boyce will face up to 30 years in prison at his sentencing on Tuesday.