Aliya Summary: G‑d gives the commandments of Kosher, explaining how to distinguish between kosher and non-kosher animals, fish, and birds. Kosher animals must chew their cud and have cloven feet. The Torah lists four animals that have only one of these attributes, but not both, and are therefore non-kosher. Kosher fish must have fins and scales. The Torah then gives a list of species of non-kosher birds, and species of kosher locust. The Torah then discusses the ritual impurity caused by coming in contact with the carcass of a non-kosher animal, as well as certain species of rodents and amphibian creatures.
If the Torah only prohibited fish without scales, one would obviously have to examine fish before declaring it Kosher. Why, then, are we commanded to examine the fish, if it has to be done anyway? Rabbi Chananya b. Akashya answers that “G-d wanted to benefit Yisrael, therefore He heaps upon us Torah and Mitzvot”, even when we’d do them anyway.