LYON, FRANCE -- A French cardinal said Thursday he did not understand why he was found guilty of covering up sexual abuse of children, as an appeals court hearing began that will decide whether to uphold his conviction.

Cardinal Philippe Barbarin tried to resign after the original conviction in March for failing to report a predator priest to police. But Pope Francis refused to accept the resignation until the appeals process is complete.

Barbarin, the archbishop of Lyon, had been given a six-month suspended sentence for "non-denunciation of sexual violence against minors."

Barbarin told the court he filed an appeal because "I cannot see clearly what I am guilty of."

The appeal occurs at a time of increasing scrutiny around the world of the Catholic Church's role in hiding abuse.

The case involves French priest Bernard Preynat, who has admitted to abusing Boy Scouts from the 1970s to 1990s.

Several church officials were accused of covering up for Preynat over many years, but some of the accusations were outside the statute of limitations and only Barbarin was convicted.

The cardinal's lawyer, Jean-Felix Luciani, said there was no legal basis for the original decision and that "we hope that at the next step, justice will be done."

The case against Barbarin hinges on a 2014 discussion with Alexandre Hezez, who told the cardinal about sexual violence he had suffered in the 1980s by Preynat during scout camps. Hezez felt the priest should no longer lead a parish.

The Lyon court found in March that Barbarin, "in wanting to avoid scandal caused by the facts of multiple sexual abuses committed by a priest ... preferred to take the risk of preventing the discovery of many victims of sexual abuse by the justice system, and to prohibit the expression of their pain."

Barbarin told the appeal hearing that he followed Vatican instructions following the 2014 discussion with Hezez. He suggested he could not have done more.

Preynat was moved to another parish and continued to work with children until his retirement in 2015.

Preynat is believed to have abused as many as 85 boys. He will be tried in Lyon in January on charges of sexual assault of minors.

In July, France's Catholic Church pronounced him guilty of sexually abusing multiple Boy Scouts over several years and defrocked him, an unusually strong move that reflects France's growing reckoning with clergy sex abuse.