Ali radhiallahu `anhu related that the Messenger of Allah sallallahu `alayhi wa sallam said, "It is part of a man's sound practice of Islam that he leave alone that which is of no concern to him." [At-Tirmidhi, Ibn Majah]

Ibn ‘Abbaas, radhiallahu `anhuma, said: "Achieving the following five matters is more beneficial than owning the best types of horses:

1. Not involving yourselves in conversations that do not concern you, as there is no guarantee that you would not sin therein.

2. Not talking about things that do concern you, until you find the proper time; as a person may talk about a matter that does concern them but at the wrong time and therefore produce a bad consequence.

3. Not arguing with a wise or a foolish person, as the wise person would desert you and the foolish person would humiliate you.

4. Mentioning your brother, in his absence, with things with which you would wish him to mention you with in your absence - and forgiving him for that which you would wish him to forgive you for.

5. Performing the actions of one who is certain that he would be rewarded for the good and punished for the bad that he does."

The Messenger of Allah sallallaahu ‘alaihi wa sallam had advised Abu Dharr, radhiallahu `anhu, saying: "Stay silent for long periods, as this keeps Satan away from you and helps you in the practice of your religion."

He sallallaahu ‘alaihi wa sallam also said: "No servants of Allah’s belief will be correct until his heart is corrected, and his heart will never be corrected until his tongue is."