Speak Good or Remain Silent
The discipline of speech: either say something beneficial or maintain silence.
The Prophet (PBUH) said: 'Whoever believes in Allah and the Last Day, let him speak good or remain silent.' This hadith establishes speech discipline as a mark of faith. Words can build or destroy, heal or wound, guide or mislead. Before speaking, the believer should consider: Is it true? Is it beneficial? Is it kind? If speech fails these tests, silence is better. The Prophet also said that most of what takes people to Hell is the harvest of their tongues. Mindful speech protects relationships, reputation, and spiritual state.
Whoever believes in Allah and the Last Day, let him speak good or remain silent.
Al-Ghazali dedicated chapters of his Ihya to the diseases of the tongue, calling it the most dangerous organ due to its power to cause harm.
Sahih Bukhari
Written about in
- What Islam says about what to say and what to leave unsaid
The rule is binary and it is attached to belief itself, not to manners. The filter supplied with it is three questions asked before speaking — is it true, is it beneficial, is it kind — and failing any one of them sends you to silence.