‘Abdullah ibn ‘Amr ibn al-‘Aas narrated that the Messenger of Allah (ﷺ) said,
مَنْ صَمَتَ نَجَا
“Whoever is silent is saved”
[al-Tirmidhi #2501. Imam al-Tirmidhi described it as ghareeb. Sheikh al-Albaani graded it as saheeh in Saheeh al-Tirmidi. Imam ibn Hajr al-Asqalani, in Fath al-Baari 11/351, wrote that ‘its narrators are reliable’. Imam Ahmad Shaakir graded it to have a saheeh isnaad by two chains in Musnad Ahmad (9/196, 10/140). However, others such as al-Mubaraakfoori, al-Suyooti and al-Nawawi have graded it to be da’eef.]
Sheikh al-Mubaarakfoori, in his commentary on Jaami’ al-Tirmidhi, wrote the following about this hadeeth:
قوله: (من صمت) أي سكت عن الشر (نجا) أي فاز وظفر بكل خير، أو نجا من آفات الدارين. قال الراغب: الصمت أبلغ من السكوت لأنه قد يستعمل فيما لا قوة له للنطق وفيما له قوة للنطق، ولهذا قيل لما لا نطق له الصامت والمصمت، والسكوت يقال لما له نطق فيترك استعماله. فالصمت في الأصل سلامة لكن قد يجب النطق شرعاً. ومقصود الحديث أن لا يتكلم فيما لا يعنيه ويقتصر على المهم ففيه النجاة.
His statement, “Whoever is silent” – meaning he was silent from (speaking any) evil – “he is saved” – meaning he has succeeded in every good, or he is saved from the trials of both worlds [i.e. this life and the hereafter].
Al-Raaghib said: al-samt [the word used for ‘silence’ in this hadeeth] carries more weight that al-sukoot [another, more common, word for ‘silence’] because it can be used [both] when one does not have the ability to speak and when one does possess the ability to speak, and so it is said that that when one does not speak then he is al-saamit [silent] and al-musmat [expressionless], while al-sukoot is said when he spoke and then he abandons speaking. So at its root, al-samt is safety, however one must speak according to the sharee’ah [i.e., it is not permitted to take a vow of silence, etc].
And the message of the hadeeth is to not speak about that which does not concern oneself, and to limit oneself about those matters which do concern him, for in this is salvation.
[Tuhfat al-Ahwadhi #2550]