“… And he languished in prison for a number of years more.” (Surah Yusuf, 42). According to an exegesis of this verse, Joseph (Peace be upon him) is the patron of prisoners, and prison is a sort of School of Joseph. (Madrasa-i Yusufiya)1
This interpretation was offered by one of the greatest Islamic scholars of the 20th century, Bediuzzaman Said Nursi, who devoted much of his life to the teaching of the morality of the Qur’an, and because of that earned the animosity of certain circles. Ultimately, he spent 30 years of his life in prison and exile.