וַיֹּ֣אמֶר יְהוָ֔ה כָּ֣כָה יֹאכְל֧וּ בְנֵֽי־יִשְׂרָאֵ֛ל אֶת־לַחְמָ֖ם טָמֵ֑א בַּגּוֹיִ֕ם אֲשֶׁ֥ר אַדִּיחֵ֖ם שָֽׁם׃
永恆者說：「以色列人在我所要驅逐他們去的列國中，也必這樣吃不潔淨的食物。」
Chizkuni
טמא הוא לכם, “it is ritually impure for you.” The word טמא here is not to be understood in the ritual sense of impurity, the person having contacted such animals requiring to perform purification rites before handling matters that are holy, but is an expression for something detestable. The concept of ritual impurity does not exist concerning fish. The expression טמא as clearly meaning something detestable is found in Ezekiel 4,13: “shall the Israelites eat their bread unclean in a disgusting unappetizing manner (among the nations that banish them?)”