Question: On what criteria does the Hanafi school distinguish fish from other sea creatures? Are prawn considered fish? Is it permissible to eat squid and crabs?
Answer:
In the Name of Allah, the Most Merciful and Compassionate,
In the Hanafi school, the only sea creatures that are permissible to eat are those considered fish. What the Arabs deemed to be fish at the time of revelation is the criteria in this matter. [Ibn ‘Abidin, Radd al-Muhtar; Kasani, Bada’i al-Sana’i]
Allah Most High says, “Made lawful for you is the game of the sea and eating thereof, as a benefit for you and for travelers.” [Qur’an, 5:96]
The game of the sea here is understood by the Hanafi scholars and Imams of Qur’anic exegesis to mean fish. [Jassas, Ahkam al-Qur’an; Zamakhsari, Kashaf]
Shrimp/Prawn
It is the soundest position of the Hanafi school that shrimp/prawns were customarily considered fish by the Arabs at the time of revelation. [Usmani, Takmila Fath al-Mulhim]
Squid, Crabs, and Other Seafood
Other than fish, no other sea creatures are permissible as they were not considered fish. Rather crabs, frogs, snakes, etc. were seen as vile things (khabith) and are prohibited. [Kasani, Bada’i al-Sana’i]
The Shafi’i School
In the Shafi’i school, anything that currently lives in water is permissible to eat due to the general statement of the Prophet (Allah bless him and give him peace), when asked about the seawater, “Its water is pure, and it is deceased are lawful to eat.” [Ibn Naqib, Umda al-Salik]
See the following link for more details:
Is Lobster Permissible in the Hanafi School
Hope this helps
Allah knows best
[Shaykh] Yusuf Weltch
Checked and Approved by Shaykh Faraz Rabbani