On the authority of Abu Hurayrah (رضي الله عنه), that the Messenger of Allah (صلى الله عليه وسلم) said:
Let him who believes in Allah and the Last Day speak good, or keep silent….
[Bukhari and Muslim]
Speech Therapy [Exhortation]
It is reported that a man saw Ibn ʿAbbās – Allāh be pleased with them – holding the tip of his tongue saying:
Woe to you, say what is good and you will reap gain, and be silent from speaking evil and you will be safe.
The man asked him:
O Ibn ʿAbbās, what is the matter that I see you holding the tip of your tongue saying such-and-such?
It has reached me that the servant of Allāh will not be as angry at anything on the Day of Resurrection as he will be at his tongue.
[Imām Aḥmad, Al-Zuhd p236]
It is reported that ʿAbdullāh b. ʿAmr b. Al-ʿĀs – Allāh be pleased with them – said:
Leave alone what you have nothing to do with, and do not speak about what does not concern you, and secure your tongue like you secure your money.
[Ibn Ḥibbān Al-Bustī, Rawḍatu Al-ʿUqalāʾ 1:55.]
‘Umar b. Al-Khattāb once entered upon Abū Bakr – Allāh be pleased with them both – and found him pulling at his tongue. He said, “Oh, what are you doing?” Abū Bakr replied, “It is this (i.e my speech) that has brought me so much trouble.”
[Mālik, Al-Muatta 2:988]
Nine Things to Say Often
It is reported that Muḥammad [Ibn Sīrīn] – Allāh have mercy him – said:
We were once in the house of ʿAlqamah b. Qays. Rabīʿ b. Ḵuthaym entered upon us and sat in a corner of the house. Then he said, “Speak only a little except for nine things: subḥānallāh, al-ḥamdulillāh, lā ilāha illallāh, Allāhu ʾakbar, reciting the Qurān, enjoining good, forbidding wrong, asking Allāh for what is good and seeking His protection from harm (evil).”
[Hannād b. Al-Sarīy, Al-Zuhd #1108.]
Do not forget your character and speech
It is reported that Abû Hurayrah – Allâh be pleased with him – used to say:
Whoever does not think that his speech is part of his deeds and that his character is part of his religion will be destroyed without even realizing.
[Ibn Abî Al-Dunyâ Dham Al-Kadhib wa Ahlî article 94.]