Imam Shafi’i:

If you want to fix your heart, or would like to see improvement in your child or friend, or anyone for that matter, then direct them to places where the Qur’an is recited and direct them to be in the company of the Qur’an.

Allaah will then cause them to become better, regardless of whether they want to or not!

Source: Hilyat al-Awliya’ (v. 9, p. 123)