Bismillahi Al-Rahmani Al-Rahim
As for the hadith "I used to give you a dispensation to use the skins of
dead animals. If this writing of mine reaches you: do not use the skins and
sinew of dead animals" then baha uddin mentions that Tirmidhi said: i heard
Ahmad ibn al-hasan say: Ahmad ibn hanbal used to rely on this hadith due to
that which is in it two months before his death and he (Ahmad) used to say:
this is the final position of the Prophet (SAW), then Ahmad left this
hadith when they became uncertain of its isnaad since some of them narrated
it and said: from Abdullah ibn Ukaim from scholars of Juhainah.
Baha uddin then goes on to mention the other opinion and puts forward its
Ibn Taymiyah says that it is said that the concession was for the madbugh
and other than it and due to this reason a group - from them az-Zuhri and
others - regarded it permissible to use the skin of a dead animal before
tanning, holding to the general statement in the hadith of maimunah and his
saying (SAW) in it: "only the eating of the dead animal has been made
unlawful". The wording of this hadith shows the prohibition but does not
include the skin. Also Ahmad relates in his musnad on the authority of ibn
Abbas who said: "A sheep died which belonged to sawdah bint zamah so she
said: O Messenger of Allah (SAW) fulanah has died - meaning the sheep - so
he said (SAW): "you should have taken its musk!" so she said: should i take
the musk of a sheep that has died? So he said to her (SAW): He only said: "
I do not find in that which has been revealed to me the prohibition of food
that is eaten except ...."[al-Anam: 145] and indeed you are not eating from
it, if you tan it you can benefit from it" [Ahmad: 1/327, 328] ...
This hadith shows that the prohibition did not include the skin and that
tanning was mentioned to keep and preserve the skin not because it was a
condition for its purity. Thus the concession for juhainah in this was the
abrogation of this i.e. the using the skin without tanning. ....... Ibn
Taymiyah then goes on to cite more proof for this position.
Ibn Taymiyah also says concerning his opinion that it is a saying in the
madhab and it is held by a group of the fuqaha al-hadith.
Each of the books of fiqh will give their respective tarjih of the sayings
of Imam Ahmad if they mention them. Just because that scholar doesn't see
this opinion as being the strongest, why does this mean it is not from the
madhab? Not the choice of the majority of scholars as ibn Taymiyah states
yes, but not from it? The stronest opinion in the madhab needs tarjih of
the sayings of Imam Ahmad and this can differ from scholar to scholar but
how can a saying of Imam Ahmad be ruled out of the madhab just because most
later scholars following his way haven't used it?
Using the famous opinion in the madhab would also make it very difficult
for people in the west. But this other opinion of Imam Ahmad with its
proofs makes it easier for the Muslims and allows them to stick with their
madhab at the same time.