Sayyidah Umm Darda’ (may Allah be pleased with her) narrates from Sayyiduna Abu Darda’ (may Allah be pleased with him) that the Prophet Muhammad (peace and blessings be upon him) said:“On the Day of Resurrection, the heaviest thing to be placed in the believer’s record of deeds will be good character, and indeed Allah Almighty dislikes the person who is foul-mouthed and uses obscene language.”

Lady Aisha Siddiqa (may Allah be pleased with her) narrates: A man sought permission to enter upon the Prophet (peace and blessings be upon him). When the Prophet (peace and blessings be upon him) heard his voice, he said to Lady Aisha (may Allah be pleased with her): "This is a bad person" (the narrator is in doubt, perhaps these are the words), "he is a bad member of his family." When that person came in, the Prophet (peace and blessings be upon him) treated him kindly. When he left, Lady Aisha (may Allah be pleased with her) spoke to the Prophet (peace and blessings be upon him) about this. Lady Aisha (may Allah be pleased with her) said: "You said: 'This is a bad person' (the narrator is in doubt, perhaps these are the words), 'he is a bad member of his family,' but when he came in, you treated him kindly." The Prophet (peace and blessings be upon him) said: "O Aisha (may Allah be pleased with her)! The worst among people is the one whom people avoid because of his bad language."

Sayyidah Aisha Siddiqa (may Allah be pleased with her) narrates: The Prophet Muhammad (peace and blessings be upon him) said: "The most disliked person in the sight of Allah Almighty is the one who is extremely quarrelsome."

Sufyan bin Abdullah Thaqafi (may Allah be pleased with him) narrates: He said, "O Messenger of Allah (peace be upon him)! Tell me about something which I may hold firmly." The Prophet (peace be upon him) said: "Say, 'My Lord is Allah,' and then remain steadfast upon it." He said, "O Messenger of Allah (peace be upon him)! Of what do you fear most concerning me?" The Prophet (peace be upon him) pointed towards his tongue and said this.

Sayyiduna Sufyan bin Abdullah Thaqafi (may Allah be pleased with him) narrates: I submitted, "O Messenger of Allah (peace and blessings of Allah be upon you)! Please tell me about something which I may hold firmly." The Prophet (peace and blessings of Allah be upon him) said: "Say, 'My Lord is Allah,' and then remain steadfast." I submitted, "O Messenger of Allah (peace and blessings of Allah be upon you)! What do you fear most for me?" The narrator states: The Prophet (peace and blessings of Allah be upon him) held his tongue and then said: "This."

(Imam Ibn Hibban, may Allah have mercy on him, says:) The Prophet (peace and blessings of Allah be upon him) holding his tongue with his blessed hand and saying: "This." means that the Prophet (peace and blessings of Allah be upon him) intended to refer to the word "tongue." The Prophet (peace and blessings of Allah be upon him) knew about the matter which he had to teach the people, so the Prophet (peace and blessings of Allah be upon him) began with himself regarding acting upon that knowledge about which he was asked, and he informed the questioner that what he feared most for that person was this—that a person with a tongue can fall into difficulty. And he (peace and blessings of Allah be upon him) instructed him to keep control over his tongue and not to let it loose. Thus, the Prophet (peace and blessings of Allah be upon him) first acted upon what he had to teach, so that he (peace and blessings of Allah be upon him) could explain the ranks of knowledge and teaching in detail.

Sufyan bin Abdullah Thaqafi (may Allah be pleased with him) narrates: I said, "O Messenger of Allah (peace be upon him)! Tell me about something which I may hold firmly." The Prophet (peace be upon him) said: "Say: My Lord is Allah, and then remain steadfast." The narrator says: I asked, "O Messenger of Allah (peace be upon him)! What do you fear most for me?" So the Prophet (peace be upon him) held his tongue and said: "This."

Sayyiduna Sahl bin Sa’d (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said:“Whoever guarantees for me (control over) what is between his jaws (i.e., his tongue), I guarantee Paradise for him.”

Sayyiduna Sufyan bin Abdullah Thaqafi (may Allah be pleased with him) narrates: I said, "O Messenger of Allah (peace be upon him)! Tell me about something which I may hold firmly." The Prophet (peace be upon him) said, "Say: My Lord is Allah, then remain steadfast." I said, "O Messenger of Allah (peace be upon him)! What do you fear most for me?" The Prophet (peace be upon him) held his tongue and then said, "This."

The narrator named Ma'iz is Ma'iz bin Abdur Rahman; this has been stated by Zubaidi, and this narrator is reliable.

Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said: "Whoever is protected from the evil of that which is between his jaws (the tongue) and that which is between his legs (the private parts), will enter Paradise."

Sayyiduna Abu Bakrah (may Allah be pleased with him) narrates that the Prophet Muhammad (peace and blessings be upon him) said: "Foul language is a part of harshness, and harshness leads to Hell. Modesty is a part of faith, and faith will be in Paradise."