(CNN)Sheikh Salman al-Awda waited at his Riyadh home for Prince Mohammed bin Salman. It was 2012 and the charismatic preacher received the then 27-year-old prince with little fanfare.
MBS once sought advice from this cleric. Now Saudi prosecutors want him executed
"We didn't think the visit was a big deal," recalled Awda's son, Abdullah Alaoudh, a Washington-based legal scholar at Georgetown University. "He was just a regular prince."
Despite his obvious ambition, bin Salman was considered a political novice. His father was the governor of Riyadh and not yet king, and, in the eyes of the country's political class, he was just another member of Saudi Arabia's thousands-strong royal family. The prince who would later become known by his initials, MBS, appeared enthusiastic about Awda's ideas for change in Saudi Arabia, according to Alaoudh.
In this meeting and at least two other meetings to come -- including one in the royal court alongside the future King Salman -- Awda, who was 55 at the time, extolled the virtues of reform and inclusive governance, according to Awda's son.
Five years later, King Salman appointed his son as the Crown Prince. Three months after MBS was promoted, Awda was arrested as part of a crackdown overseen by a security agency established by the newly-anointed heir to the throne.
After a year of pre-trial detention, in September 2018, Saudi Arabia's General Prosecutor presented Awda with a list of 37 charges and recommended the death penalty. This Sunday, the cleric will return to court, where the judge may decide on whether to make a ruling in the case, and if found guilty, sentenced, according to his family.
The cleric has spent nearly two years in solitary confinement, his son told CNN. For the first few months of his detention, "his legs were shackled and he was handcuffed. The prison guards used to throw his meals at him," said Alaoudh.
Awda was held incommunicado for the first six months of his arrest. When his family was finally allowed to visit him, he told them that he was frequently deprived of sleep and food, Alaoudh added.
He eventually signed documents, likely forced confessions, that he could no longer understand because of his poor mental and physical state, according to his son. His father told the family that he "signed some documents but had no idea what they said."
Saudi Arabia has frequently been accused of making prisoners sign confessions under duress.
Alaoudh's blood pressure shot up, and so did his cholesterol levels. He was hospitalized for a few days, according to his son. "It felt to him like a slow death," said Alaoudh.
When the United Nations raised concerns in 2017 that torture had been used to obtain confessions, the Saudi government responded with a letter denying the claims.
According to the charge sheet, Awda's confessions related to his activism in favor of a constitutional monarchy, and his alleged association with high-profile members of the Muslim Brotherhood.
Saudi authorities did not immediately respond to CNN's request for comment about the charges made against Awda.
Awda's 2017 detention wasn't his first. Early in his career, Awda aligned himself with the kingdom's much-feared Sahwa (The Awakening) movement. They were the so-called Islamic revivalist clerics credited with ushering in ultraconservative religious p