Why did Elder Ben Huan go to prison?

From Hebei to Wutai Mountain, 5 1 year-old was unjustly imprisoned for 22 years; He copied 19 Buddhist scriptures with his own blood; After his death, he became a colorful relic, and100000 followers saw him off. This man is Elder Ben Huan, who is known as the legend of Buddhism in China. However, Elder Ben Huan said indifferently, "Prison is a bad karma created in previous lives, so I went to prison to repent", hoping to help you.