2136 - Suwayd ibn Nasr informed us, saying: Abdullah informed us, from Ismail, from Muhammad ibn Sa'd, from his father, who said: The Messenger of Allah, peace and blessings be upon him, said: "The month is like this, and like this, and like this" — meaning twenty-nine (days).

Yahya ibn Sa'id and others narrated it from Ismail, from Muhammad ibn Sa'd, from the Prophet, peace and blessings be upon him:

2137 - Ahmad ibn Sulayman informed us, saying: Muhammad ibn Ubayd narrated to us, saying: Ismail narrated to us, from Muhammad ibn Sa'd ibn Abi Waqqas, who said: The Messenger of Allah, peace and blessings be upon him, said: "The month is like this, and like this, and like this" — and Muhammad ibn Ubayd clapped his hands describing it three times, then on the third time he folded the thumb of his left hand. Yahya ibn Sa'id said: I said to Ismail: "From his father?" He said: "No."

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= Muslim, as will follow. Abu Hatim said in "Al-'Ilal" 1/255 (754): The connected version is more likely correct, for the trustworthy narrators have agreed upon it. Al-Daraqutni said in "Al-'Ilal" 4/359: Ismail ibn Abi Khalid sometimes connected it and sometimes sent it (as mursal). It is in "Al-Sunan al-Kubra" under number (2456).

Ahmad (1594), Muslim (1086): (26), and Ibn Majah (1657) also narrated it via the path of Muhammad ibn Bishr, with this chain.

Ahmad (1595) and Muslim (1086) also narrated it via the path of Zaidah ibn Qudamah, from Ismail, with it.

Al-Sindi said: His statement "and he decreased on the third" — the meaning is that that month, or the month, is sometimes twenty-nine, and likewise everything that comes of this nature. And Allah knows best.

(1) Its chain is authentic, and the discussion of it has already preceded in the previous narration. Abdullah: he is Ibn al-Mubarak.
It is in "Al-Sunan al-Kubra" under number (2457).
Ahmad (1596) and Muslim (1086) also narrated it via the path of Ibn al-Mubarak, with this chain.

(2) Added after it in "Al-Tuhfah" (3920): The hadith of Yahya is more correct in my view.

(3) An authentic hadith, and this chain has trustworthy narrators, except that it is interrupted (munqati'), and the discussion of it has already preceded in narration (2135). It is in "Al-Sunan al-Kubra" under number (2458).