Why is pork a sin?

Reasons for the Prohibition of Pork

As stated in Leviticus 11:3, certain animals such as cows, sheep, and deer can be consumed because they possess divided hooves and chew their cud. In contrast, pigs are considered unclean since they do not chew their cud. This prohibition against eating pork is reiterated in Deuteronomy 14:8.