Question: Shellfish and eels cannot be eaten according to what?
About the article "Seafood", section "In religion".

Candidate passages:
In Islam, the Shafi'i, Maliki and Hanbali schools allow the eating of shellfish, while the Hanafi school does not allow it in Sunni Islam.
Nor does the Shi'ite school (Ja'fari) allow it.
The Jewish laws of Kashrut forbid the eating of shellfish and eels.
According to the King James version of the bible, it is alright to eat finfish, but shellfish and eels are an abomination and should not be eaten.
Since early times, the Catholic Church has forbidden the practice of eating meat, eggs and dairy products at certain times.
Thomas Aquinas argued that these "afford greater pleasure as food fish, and greater nourishment to the human body, so that from their consumption there results a greater surplus available for seminal matter, which when abundant becomes a great incentive to lust."
For the most part Islamic dietary laws allow the eating of seafood, though the Hanbali forbid eels, the Shafi forbid frogs and crocodiles, and the Hanafi forbid bottom feeders such as shellfish and carp.
The Jewish laws of Kashrut forbid the eating of shellfish and eels.
According to the King James version of the bible, it is alright to eat finfish, but shellfish and eels are an abomination and should not be eaten.
Since early times, the Catholic church has forbidden the practice of eating meat, eggs and dairy products at certain times.
Thomas Aquinas argued that these "afford greater pleasure as food fish, and greater nourishment to the human body, so that from their consumption there results a greater surplus available for seminal matter, which when abundant becomes a great incentive to lust."
In the United States, the Catholic practice of abstaining from meat on Fridays has popularized the Friday fish fry, and parishes often sponsor a fish fry during Lent.
In predominantly Roman Catholic areas, restaurants may adjust their menus during Lent by adding seafood items to the menu.
The dish is traditionally prepared using the freshwater eels native to Britain.
Typically, the eels are chopped (shucked) into rounds and boiled in water and vinegar, to make a fish stock, with nutmeg and lemon juice before being allowed to cool.
The eel is a naturally gelatinous fish so the cooking process releases proteins, like collagen, into the liquid which solidify on cooling to form a jelly, though gelatin may be added in order to aid this process.
Recipes for jellied eels are individual to particular London pie and mash shops, and also street sellers; however, traditional recipes for authentic Victorian jellied eels all have common ingredients and cooking methods.
What alters is the choice of herbs and spices used to flavour the dish.
Jellied eels are often sold with pie and mash—another traditional East End food—and eaten with chilli vinegar or with malt vinegar and white pepper. 
Little information about predation on eels has been published.
It was reported that elvers and small yellow eels are prey of largemouth bass and striped bass, although they were not a major parts of these predators' diet.
Leptocephali, glass eels, elvers, and small yellow eels are likely to be eaten by various predatory fishes.
Older eels are also known to eat incoming glass eels.
They also fall prey to other species of eels, bald eagles, gulls, as well as other fish-eating birds  
According to Jewish law, the sciatic nerve (Hebrew: Gid hanasheh) cannot be eaten, to commemorate the Jacob's victory over an Angel.