I say: It seems that he did not notice that Ibn Lahīʿah’s hadith was narrated from him by Ibn al-Mubārak; otherwise, he would not have declared it weak. And Allah knows best.

660 — “Recite the Quran, for you will be rewarded for it. I do not say that Alif Lām Mīm is one letter; rather, alif is ten, lām is ten, and mīm is ten—making thirty.”

It was narrated by al-Khaṭīb in al-Tārīkh (1 / 285) and al-Daylamī (1 / 1 / 13), through the route of Muḥammad ibn Aḥmad ibn al-Junayd, who said: Abū ʿĀṣim informed us, from Sufyān, from ʿAṭāʾ ibn al-Sāʾib, from Abū al-Aḥwaṣ, from ʿAbdullāh, who said: The Messenger of Allah, peace and blessings be upon him, said it.

This is a good chain of transmission. Its narrators are trustworthy and are narrators of the Ṣaḥīḥ collections, apart from Ibn al-Junayd. Al-Khaṭīb included his biography and said: “He was a truthful shaykh.” Others also declared him trustworthy.

However, its attribution to the Prophet was disputed. Al-Dārimī narrated it in his Sunan (2 / 429): Abū ʿĀmir Qubayṣah narrated to us; Sufyān informed us from him, with similar wording, except that he stopped it at Ibn Masʿūd.

What supports its attribution to the Prophet is that al-Tirmidhī narrated it (4 / 53) through the route of Muḥammad ibn Kaʿb al-Quraẓī, who said: I heard ʿAbdullāh ibn Masʿūd say: The Messenger of Allah, peace and blessings be upon him, said: “Whoever recites a letter from the Book of Allah shall have ...” He then cited a hadith with similar wording and said: “A good, authentic hadith.”

I say: Its chain of transmission is also good. I have traced it in my annotation on al-Ṭaḥāwiyyah (p. 201, fourth edition, published by al-Maktab al-Islāmī) and in al-Mishkāh (2137).