Allah caused a great whale, known as al-‘anbar, to come to them. They found it on the shore, and it was enormous: a group of them could sit inside its eye socket, so vast was it. They took one of its ribs, set it upright, and loaded their largest camel, which then passed beneath the rib. They ate from it until they were full, and they brought some of it to the Prophet ﷺ. (1)

Likewise, there is the hadith of Ibn Umar, may Allah be pleased with him: “Two kinds of carrion and two kinds of blood have been made lawful for us. As for the two kinds of carrion, they are locusts and whales.” (2) Thus, the lawfulness of fish and whales without ritual slaughter is established by evidence from the Quran and the sunnah.

They are lawful even if they contain blood, and it is well known that large fish contain blood.

If you ask: How can it be lawful when it contains congealed blood, whereas you have explained the prohibition of carrion and similar things on the grounds that they contain harmful congealed blood?

We reply: Harm and the absence of harm lie in the hand of the One in Whose hand are benefit and harm: Allah, Glorified and Exalted is He. When Allah permits carrion for His servants, we are certain that its congealed blood is not harmful. This is part of Allah’s wisdom, for catching fish in such a way as to ritually slaughter it is difficult, or even impossible. Therefore, out of His wisdom and mercy, Allah, Glorified and Exalted is He, has permitted this fish for His servants without ritual slaughter.