Why did Froissart think John Ball was 'a mad priest'?

Froissart referred to John Ball as a "mad priest" due to Ball's radical views and fiery sermons that incited the Peasants' Revolt of 1381 in England. Ball advocated for social equality and challenged the established social order, which alarmed many, including Froissart. His passionate rhetoric and calls for rebellion against the nobility were perceived as extreme, leading Froissart to label him as mad for his revolutionary ideas.