Abd Allah—for he asked him about the hadith of Kathir ibn Abd Allah, from his father, from his grandfather, concerning the hour on Friday in which [supplication] is hoped for (1): he said: a hasan hadith, except that Ahmad ibn Hanbal used to criticize Kathir and declare him weak. He said: Yahya ibn Sa'id also narrated from Kathir. And al-Tirmidhi had asked al-Bukhari about his hadith concerning the takbir in the prayer of the two Eid festivals (2), and he said: there is nothing in this chapter more authentic than this (and by it I speak) (3). Al-Tirmidhi deemed hasan for him four hadiths: these two hadiths, the hadith "Whoever revives my Sunnah," and the hadith "Indeed faith will retreat to Medina," and he deemed sahih for him the hadith of the chapter. Ibn Khuzaymah also included him in his Sahih. And it is al-Tirmidhi's practice that a hasan hadith, when narrated through more than one chain, is elevated to the degree of sahih. He explicitly stated this when mentioning the hadith of Muhammad ibn Amr, from Abu Salamah, from Abu Hurayrah, from the Prophet, peace be upon him, that he said: "Were it not that I would burden my ummah, I would have commanded them to use the siwak at every prayer." He deemed it sahih, then said: the hadith of Abu Hurayrah is only sahih because it has been narrated through more than one chain. And it is al-Bukhari's practice to deem hasan the individual narrations of Muhammad ibn Amr, and he deemed this one sahih and explained the reason for that, for it was narrated through more than one chain. Ibn al-Salah affirmed this principle in his 'Ulum al-Hadith (4). Thus the hadith of Kathir ibn Abd Allah concerning the reconciliation is strengthened by the hadith of Abu Hurayrah, and for that reason al-Tirmidhi deemed it sahih. And God knows best.

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(1) Al-Tirmidhi (490).
(2) Al-Tirmidhi (536), and see al-'Ilal al-Kabir 1/287 (87).
(3) What is between the parentheses is an addition from al-Tirmidhi's al-'Ilal 1/288.
(4) P. 104.