In a recent question regarding the consumption of whale, the answer given was that it is impermissible and that the Companions ate of it due to dire necessity. However, why did the Prophet Sallallahu alayhi wasallam also partake of it and furthermore, it is mentioned that the Companions ate until they gained a great deal of weight?
Furthermore, Bukhari narrates that the Prophet said “Eat, for it is food Allah has brought out for you, and feed us if you have some of it.” So some of them gave him (of that fish) and he ate it.” (Sahih al-Bukhari, no: 4104)
In Muslim, the narration of Jabir says that "We lived on it for a month - and there were three hundred of us - eating until we were full"
Al-jawab billahi at-taufeeq (the answer with Allah's guidance)
According to the Hanafi Madhab, only fish is Halal. All the other sea animals are Haram. (Fataawa Hindiyyah Vol.5 Pg.357)
The sea animal that is described in the Hadith, refers to a huge and gigantic fish which was an extraordinary act of Allah’s command. However, Whales are mammals, not fish, hence Haram in the Hanafi Madhab.
Narrated Wahab bin Kaisan:
Jabir bin Abdullah said, "Allah's Apostle sent troops to the sea coast and appointed Abu 'Ubaida bin Al-Jarrah as their commander, and they were 300 (men). We set out, and we had covered some distance on the way, when our journey food ran short. So Abu 'Ubaida ordered that all the food present with the troops be collected, and it was collected. Our journey food was dates, and Abu Ubaida kept on giving us our daily ration from it little by little (piecemeal) till it decreased to such an extent that we did not receive except a date each." I asked (Jabir), "How could one date benefit you?" He said, "We came to know its value when even that finished." Jabir added, "Then we reached the sea (coast) where we found a fish like a small mountain. The people (i.e. troops) ate of it for 18 nights (i.e. days). Then Abu 'Ubaida ordered that two of its ribs be fixed on the ground (in the form of an arch) and that a she-camel be ridden and passed under them. So it passed under them without touching them."
Narrated Jabir bin 'Abdullah:
Allah's Apostle sent us who were three-hundred riders under the command of Abu Ubaida bin Al-Jarrah in order to watch the caravan of the Quraish pagans. We stayed at the seashore for half a month and were struck with such severe hunger that we ate even the Khabt (i.e. the leaves of the Salam, a thorny desert tree), and because of that, the army was known as Jaish-ul-Khabt. Then the sea threw out, an animal (i.e. a fish) called Al-'Anbar and we ate of that for half a month, and rubbed its fat on our bodies till our bodies returned to their original state (i.e. became strong and healthy). Abu Ubaida took one of its ribs, fixed it on the ground; then he went to the tallest man of his companions (to let him pass under the rib). Once Sufyan said, "He took a rib from its parts and fixed it, and then took a man and camel and they passed from underneath it (without touching it). " Jabir added: There was a man amongst the people who slaughtered three camels and then slaughtered another three camels and then slaughtered other three camels, and then Abu 'Ubaida forbade him to do so.
We set out in the army of Al-Khabt and Abu Ubaida was the commander of the troops. We were struck with severe hunger and the sea threw out a dead fish the like of which we had never seen, and it was called Al-'Anbar. We ate of it for half a month. Abu Ubaida took (and fixed) one of its bones and a rider passed underneath it (without touching it). (Jabir added:) Abu 'Ubaida said (to us), "Eat (of that fish)." When we arrived at Medina, we informed the Prophet about that, and he said, "Eat, for it is food Allah has brought out for you, and feed us if you have some of it." So some of them gave him (of that fish) and he ate it.
(Bukhari, Book: Al Maghazi (military expeditions of the Prophet, Sallallahu Alaihi Wasallam))