Here are two Ḥasan (Good) or Ṣaḥīḥ (Authentic) ḥadīth about reciting salawāt removes nifāq. Also, in the second ḥadīth it says that the Prophet (صلى الله عليه وآله وسلم) says to “raise your voices” when saying salawāt, which this can be seen in Shī`ah centers all over the world. Both aḥādīth have the same chain of narrators.
عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ عَبْدِ اللَّهِ بْنِ سِنَانٍ عَنْ أَبِي عَبْدِ اللَّهِ ع قَالَ قَالَ رَسُولُ اللَّهِ ص الصَّلَاةُ عَلَيَّ وَ عَلَى أَهْلِ بَيْتِي تَذْهَبُ بِالنِّفَاق
`Alī b. Ibrāhīm[1] from his father[2] from Ibn Abī `Umayr[3] from `Abd Allāh b. Sinān[4] from Abī `Abd Allāh said, the Messenger of Allāh (صلى الله عليه وآله وسلم), “Salāh (Prayers) upon me and upon my Ahl al-Bayt removes hypocrisy (nifāq)”[5]
ابْنُ أَبِي عُمَيْرٍ عَنْ عَبْدِ اللَّهِ بْنِ سِنَانٍ عَنْ أَبِي عَبْدِ اللَّهِ ع قَالَ سَمِعْتُهُ يَقُولُ قَالَ رَسُولُ اللَّهِ ص ارْفَعُوا أَصْوَاتَكُمْ بِالصَّلَاةِ عَلَيَّ فَإِنَّهَا تَذْهَبُ بِالنِّفَاقِ
[`Alī b. Ibrāhīm[6] from his father[7] from] Ibn Abī `Umayr[8] from `Abd Allāh b. Sinān[9] from Abī `Abd Allāh, that he heard him say that the Messenger of Allāh (صلى الله عليه وآله وسلم) said, “Raise your voices in Salāh (prayers) upon me, for it removes hypocrisy (nifāq)”[10]
[1] `Alī b. Ibrāhīm b. Hāshim al-Qummī is thiqah (trustworth) according to al-Najāshī (See: al-Najāshī, al-Rijāl, pg. 260, person # 680) and al-Ḥillī (See: al-Ḥillī’s al-Khulāṣah, pg. 100, person #45).
[2] Ibrāhīm b. Hāshim is praised according to al-Najāshī (See: al-Najāshī, al-Rijāl, pg. 16, person # 18), al-Ṭūsī (See: al-Ṭūsī, al-Fihrist, pg. 12, person # 6) and al-Ḥillī (See: al-Ḥillī’s al-Khulāṣah, pg. 5, person #9).
[3] Muḥammad b. Abī `Umayr is thiqah (trustworthy) according to al-Najāshī (See: al-Najāshī, al-Rijāl, pg. 326, person # 887), al-Ṭūsī (See: al-Ṭūsī, al-Fihrist, pg. 404, person # 618 & al-Ṭūsī, al-Rijāl, pg. 265, person # 5413), and al-Ḥillī (See: al-Ḥillī’s al-Khulāṣah, pg. 140, person #16).
[4] `Abd Allāh b. Sinān is thiqah (trustworthy) according to al-Najāshī (See: al-Najāshī, al-Rijāl, pg. 214, person # 558), al-Ṭūsī (See: al-Ṭūsī, al-Fihrist, pg. 291, person # 434) and al-Ḥillī (See: al-Ḥillī’s al-Khulāṣah, pg. 104-105, person #15).
[5] al-Kulaynī, al-Kāfī, vol. 2, pg 492, ḥadīth # 8; al-Majlisī said this ḥadīth is Ḥasan Kal-Ṣaḥīḥ (Good like a Ṣaḥīḥ (ḥadīth)) (See: al-Majlisī, Mir’āt al-`Uqūl, vol. 12, pg. 98).
[6] Refer to footnote 1.
[7] Refer to footnote 2.
[8] Refer to footnote 3.
[9] Refer to footnote 4.
[10] al-Kulaynī, al-Kāfī, vol. 2, pg 493, ḥadīth # 13; al-Majlisī said this ḥadīth is Ḥasan Kal-Ṣaḥīḥ (Good like a Ṣaḥīḥ (ḥadīth)) (See: al-Majlisī, Mir’āt al-`Uqūl, vol. 12, pg. 99).
Bibliography
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al-Kulaynī. al-Kāfī. Ed. `Alī Akbar al-Ghaffārī. 3rd. 8 vols. Tehran: Dār al-Kutub al-Islāmiyyah, 1388.
al-Majlisī. Mir’āt Al-`Uqūl. 26 vols. Tehran: Dār al-Kutub al-Islāmiyyah, 1410.
al-Najāshī. Rijāl. Ed. Musa al-Shabiri al-Zanjani. 5. 1 vols. Qum: Mu’assasah al-Nashr al-Islāmī, 1416.
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—. al-Rijāl. 1st. Qum: Mu’assasah al-Nashr al-Islāmī, 1415.