The reason that led him to compile this type [of narration] in his book was that he followed the doctrine of his teacher, Imam Ahmad ibn Hanbal, in adducing a hadith that is weak to a slight degree as evidence, when nothing in the authentic [collections] sufficed in its place, and when nothing contradicted it that was more authentic than it. This is the cause that impelled him to author the book "al-Marasil" [The Mursal Narrations], in which he included "five hundred and forty-four hadiths."

Imam Abu Bakr al-Athram, the companion of Imam Ahmad, said: Abu 'Abd Allah—meaning Ahmad ibn Hanbal—would sometimes [encounter] a hadith from the Prophet, peace and blessings be upon him, in whose chain of transmission there was something [questionable], and he would act upon it if nothing more firmly established contradicted it, such as the hadith of 'Amr ibn Shu'ayb and Ibrahim al-Hajari. And sometimes he would act upon the mursal hadith if nothing contradicted it.

Imam Ibn Qayyim al-Jawziyyah mentioned—while explaining the principles that Imam Ahmad adopted and upon which he built his school of thought—and said: The fourth principle—meaning according to Imam Ahmad—is the acceptance of the mursal and the weak hadith when there is nothing in the subject matter that repels it. This is what he preferred over analogical reasoning [qiyas]. By "weak" he did not mean the false, nor the rejected [munkar], nor that whose narrator is accused [of dishonesty] such that recourse to it and acting upon it would not be permissible. Rather, the weak hadith according to him is the counterpart of the authentic [sahih] and a category among the categories of the good [hasan]. He did not divide hadith into authentic, good, and weak, but rather into authentic and weak. And the weak hadith has levels according to him. So when he found no narration [athar] in the subject matter that repelled it, nor a saying of a Companion, nor a consensus—