In the past week, around 20 have been arrested, the most famous among them are Sheikh Salman al-Odah, Awadh al-Qarni, and Ali al-Omari.
Having followed the political careers of those clerics and written a book about some of them, the arrest came as a surprise. Most of those Sahwis have been tamed by their previous experiences in prison, a natural evolution of their thinking and new circumstances.
But Crown Prince Mohammed bin Salman is clearly not convinced. On 10 September, according to a source who cannot be identified, he sent three men to arrest Salman al-Odah without any concern over his followers' reaction.
In the early 1990s, the last time al-Odah was arrested in his hometown Buraiydah in the center of Saudi Arabia, his followers and students staged the first demonstration against the detention of an "Islamist" in Saudi Arabia. The demonstration was recorded on video and kept for future generation of "Islamists" to learn from.
At the time, this was dubbed intifadat Buraiydah, the Buraiydah uprising. Al-Odah spent at least five years in prison for delivering sermons that criticized the government for inviting foreign troops to defend Saudi Arabia during the Iraqi invasion of Kuwait.
So why has al-Odah been arrested again and for what purpose?
Here we are in the realm of speculation. According to one narrative, the Saudi government wanted him to denounce Qatar and overtly defend the Saudi position. His last tweets in which he supplicated to God to bring unity among Muslim leaders immediately after the doomed phone call between Mohammed bin Salman and Sheikh Tamim of Qatar weren't taken very well in official Saudi circles.
Four days later, the sheikh is still in detention. No family member has been able to see him or find out more details about his whereabouts after three security officials picked him up and drove away.
By launching a fresh wave of "Islamist" detentions, the Saudi regime is intimidating the most famous and well-known religious figures in the country, sending a message to their followers, who have been surprisingly very quiet and dormant since the Arab uprisings of 2011.
"Islamists" made noises when the Saudi regime supported the Egyptian coup that ousted the Muslim Brotherhood and many signed a petition denouncing those who lent support to the military dictatorship.
Yet Salman al-Odah was careful not to enrage the regime. He celebrated the Arab revolutions and explained that they are overdue. When people lose hope, they go to the streets demanding their rights, he said. Freedom, justice and dignity are universal in his opinion.
While he escaped arrest at the time, he was definitely watched lest he express any opinion that would serve to mobilize Saudi youth eager to copy their Egyptian counterparts.
However, the critical moment came with the Saudi-Qatar crisis. Since June 2017, the regime has been watching and monitoring the reaction of "Islamists", all accused of being loyal to Qatar, if not on its payroll.
Al-Odah and the others remained silent, preferring not to take sides openly. But that was not enough. The Saudi regime wanted to test their loyalty and extract total submission from them. As they refrained from openly supporting the regime, the regime became increasingly suspicious, accusing them of double loyalty, and acting as a fifth Qatari column in the heart of Saudi Arabia.
This reminds us of the official Saudi narrative about the Shia of the Eastern Province. Every time they rise to demand their rights, they are accused of being an Iranian fifth column. So now the "Islamists" are treated with suspicion because they are believed to follow Qatar.
Dissent in Saudi Arabia is always treated as the conspiracy of other governments. The regime does not recognize that there might be legitimate and overdue demands that are denied. But Saudi Arabia had opposition movements long before the creation of the state of Qatar.
The Saudi regime must be feeling the pressure of the failure of its recent aggressive regional policy and domestic leadership shuffles. The man at the top, Crown Prince Mohammed bin Salman, seems to be home alone. He got rid of other competing princes, old uncles, and more experienced contemporaries. He fears his own kin and, if he stumbles, he may not find a savior.
He has antagonized the large "Islamist" movement and sidelined Salafis loyal to the regime. He marginalized them, deprived them of any real power, and undermined their authority when he promised to entertain Saudis with new singing and dancing venues that threaten their control.
Mohammed bin Salman rules with an iron fist now as other softer means have stopped being deployed. He does not care about his own family's consensus or society's approval. His multiple initiatives to revive the economy and transform Saudi Arabia may backfire and fall back on their launching pads.
The arrested "Islamists" are just the latest casualty in a struggle that is proving difficult to win for the young and inexperienced prince.
Previous beleaguered kings have fallen on two legitimacy narratives: one, celebrating the regime's commitment to Islam, or the second, highlighting its commitment to development and prosperity. Mohammed bin Salman can no longer count on either to cement his rule and enlist others in his defense.
He has alienated "Islamists" and arrested their most prolific and famous cleric while his economic transformation plans seem too overambitious to become reality anytime soon. Saudi Arabia is heading towards an unpredictable turn that may become seriously problematic.