And Ibn al-Ṣalāḥ added: Abū Zayd—the leading Mālikī scholar of his era—said, “All the manners of goodness are gathered into four hadiths:

1. ‘Whoever believes in Allah and the Last Day, let him speak good or remain silent’ (al-Bukhari 6138; Muslim 47);

2. ‘Part of the beauty of a person’s Islam is to leave what does not concern him’ (al-Tirmidhi 2317);

3. ‘Do not become angry’ (al-Bukhari 6116);

4. ‘None of you truly believes until he loves for his brother what he loves for himself’ (al-Bukhari 13; Muslim 245).”
   Thus, this hadith is one of the foundational traditions upon which Islam turns.

5. Imām al-Ghazālī said: The criterion for speech that “does not concern you” is any word that, were you to keep silent, would bring you neither sin nor harm in person or property. By uttering it you waste your time, spending moments that would be better devoted to reflection and remembrance. Whoever could take a treasure from among treasures yet settles instead for a useless clod of earth is a loser indeed.