Negative commandment · Lo Ta’aseh #179 of 613
Not to eat swarming creatures that breed in the water
שלא לאכול שרץ המים
The verse · Vayikra 11:43
אַל־תְּשַׁקְּצוּ אֶת־נַפְשֹׁתֵיכֶם בְּכׇל־הַשֶּׁרֶץ הַשֹּׁרֵץ וְלֹא תִטַּמְּאוּ בָּהֶם וְנִטְמֵתֶם בָּם
“You shall not make yourselves abominable with any creeping thing that creeps, neither shall you make yourselves unclean with them, that you should be defiled by them.”
The Rambam’s words
Not to eat swarming creatures that breed in the water, as [Leviticus 11:43] states: "Do not make yourselves detestable [by eating] any swarming creature."
שלא לאכול שרץ המים, שנאמר "אל תשקצו, את נפשותיכם, בכל השרץ" (ויקרא יא,מג).
Why · Sefer HaChinuch #164
To not eat of the swarming creatures of the waters
“It is from the roots of this commandment [that it is] because the body is an instrument of the soul — with it, it carries out its activity; without it, it can never complete its work.”
Who & when
“And [it] is practiced in every place and at all times by males and females.”
Where in the Mishneh Torah
Hilchot Forbidden Foods הלכות מאכלות אסורות