Sheikh Muhammad al-Qannâs
There are several hadîth and narrations that encourage a Muslim to safeguard his tongue and prevent it from evil.
The Muslim only speaks of righteous things; otherwise he should keep silent. Silence is better than speaking.
The Prophet (peace be upon him) said: “Whoever believes in Allah and the Hereafter should not harm his neighbor, and whoever believes in Allah and the Hereafter should honor his guest, and whoever believes in Allah and the Hereafter should either say something good or keep silent.” [Sûrah al-Bukhârî (6018) and Sahîh Muslim (47)]
And says: “The belief of someone will not be enhanced until his heart enhanced and his heart will not enhanced until his tongue enhanced, no man will enter Paradise while his neighbor does not feel saved from his evil.” [Musnad Ahmad 12575]
The Prophet (peace be upon him) said: “The servant may utter a word without giving attention to it and fell, because of it, into Fire further than the distant between the east.” [Sahîh al-Bukhârî (6477) and Sahîh Muslim (2988)]
The excessive talking in other than the remembrance of Allah will harden the heart and the further from Allah among people is the man with a hard heart.” [Sunan al-Tirmidhî (2333); he said: this is fine and strange hadîth]
`Umar b. al-Khattâb said: who excessively speaks he increases his mistakes and whose mistakes increase his sins will increase and whose sins increase Fire will deserve him more”
Abû Bakr al-Siddîq used to hold his tongue then says: “This one drove me into sins.”
Ibn Mas`ûd said: “By Allah who’s no god but Him nothing in this life deserves to be in long imprisonment except the tongue” and said: “Beware the excessive speech; it is enough for the person to express what he needs”.
Imam al-Nakh`î said: “People will go astray because of excessive money and excessive speech.”
And Allah knows best.
Source: Islam Today