"Some of the 'holy' violence alarmed even the Church. In North Africa at the turn of the fifth century, the circumcellions became notorious not only for their suicides but for their vicious attacks on those who didn't share their particular Christian beliefs. One bishop was standing next to his altar when suddenly he found himself surrounded and beaten by men with clubs. Then his attackers tore his altar apart, beat him with its remnants, before finally stabbing him in the groin. Another priest found himself dragged from his house and, once the circumcellions had him outside, they gouged out his eye. Like the tailor-made tortures that awaited sinners in Hell, where blasphemers were strung up by their tongues, there was a ghoulish appositeness to these assaults. Eyes of the erring were gouged out because those who couldn't see the true religion were 'blind' anyway. Another bishop was seized, his hands chopped off and his tongue, which had preached falsehoods, cut out.
"The circumcellions roamed widely, vandalizing property, setting light to churches and torching houses. Just when people thought that these 'warriors', as they called themselves, could not have got any worse, they invented what Augustine called a 'new and unspeakable kind of violence, a piece of cruelty deserving of the Devil Himself'. By mixing together caustic lime powder and vinegar they created a solution strong enough to burn human skin. This they took to throwing into the eyes of priests, blinding them. Nowhere was safe: if a 'traitor' - as they called those who didn't share their beliefs - was known to be at home, the circumcellions would go into their house, drag them out, and then attack them. The more unexpected the attack, the more glorious the effect.
"Festivals of the old gods were a favourite target: circumcellions raided these, smashing statues and shouting their rallying cry of Laudes Deo - 'Praise the Lord' as they went. In a moment, a joyful, drunken celebration could be reduced to sheer chaos. Like so many before and since, these men wanted religious conformity and they would stop at little to get it. Because Matthew 26:52 advised Christians to 'sheathe your sword', with almost Jesuitical precision they adopted the club as their weapon of choice. Appalling violence could thus be done while sin was avoided. Besides, a club was efficient enough: they would beat to death as many as they could before melting back into the landscape. The sticks with which these men carried out this work became their proud trademark; they called them their 'Israels'." (The Darkening Age: The Christian Destruction of the Classical World, Catherine Nixey, 2017, pp 223-24)
Required Christmas reading.