Question:
Answer:
Eating pork is not an intrinsic evil as is, say, adultery.
Eating pork becomes a sin for a Catholic when he deliberately eats it on a Lenten Friday which is also not a solemnity, given that he’s violating a Church precept to abstain from meat on such days. (A solemnity trumps the normally prescribed abstinence.) Violating this Church precept is an offense against God, because Jesus gave Peter and his papal successors the power to bind and loose (Matt. 16:18-19) and by extension to those bishops/apostolic successors in union with the pope (cf. Matt. 18:15-18). So the sin is one of disobedience against God and his Church, not because eating pork or any meat is inherently evil.
Similarly, Jews and Muslims should not be compelled to violate their respective religious precepts that forbid the consumption of pork. While we as Catholics disagree, in part, with the reasons why they abstain from pork, we respect their desire to honor God, and we defend their religious liberty to do so.
For more on this issue, see this Catholic Answers response on Lenten practices.