What is the difference between unclean and abominable? Scripture uses both of these words in Leviticus 11 and elsewhere in regards to animal flesh. It's important for believers to make a distinction between these two words in order to correctly understand Scripture, and to understand Biblical eating guidelines.
One argument you're likely to hear against following the Bible's laws concerning what we eat is that it's not sin to become unclean, and certain animals - like pigs and shellfish - are "just" unclean. The logic is if it's not sin to become unclean, it must be okay to eat something that makes you unclean. However this is not what Scripture says!
It's true that being in an unclean state is not in and of itself sin. But it's not true that that certain animals are "just" unclean. If you take a look at Leviticus 11 you can see that it lists certain animals as abominable. The Hebrew word for abomination is seqes, and it means that that thing is detestable and can be related to idol worship! The connection to idol worship is not predicated on if the person eating abominable flesh means it to be idol worship or not; the connection remains regardless of intentions. The English word abominable can mean disgusting and if you read this chapter that is mostly the impression you get...in our culture today the idea of eating animals like dogs, bats, rodents, and such is a repulsive thought. The Bible is saying that it shouldn't even cross our minds to eat these things.
Please note that nowhere in Leviticus 11 or elsewhere in the Bible does it say that if you choose to eat certain animals you will become unclean. When it talks about eating non-permissible animals it calls that an abomination! When the word 'unclean' appears later in Leviticus 11:24 it is in regards to simply touching the dead flesh of certain animals. That means you don't become unclean for petting a dog or cat or riding a horse - only if you touch or deal with the carcass of one. This certainly seems like a sensible regulation - if someone has just touched a dead racoon, you probably don't want to hold their hand or let them chop the vegetables for dinner. This passage of Scripture also gives us directions here for what happens if something unclean, like a mouse, ends up in a cooking pot.
If you touch a carcass of an unclean animal - whether that's to put bacon in a skillet or to cleanup an animal that died - you become unclean. But if you eat the carcass of one of these animals that is an abomination according to Leviticus 11:11! Doing something that the Bible says is an abomination is sin.
The Bible calls animals like dogs, pigs, horses, and monkeys unclean, and by touching their carcasses we become unclean as well. Again, being in an unclean state is not a sin, and sometimes it is unavoidable. But the Bible does not say that being in an unclean state is all the consequence there is to consuming forbidden animals. The issue with eating these things is not that we would become unclean, but that we would be in sin! It is wrong to to eat animals that the Word of God made a point of telling us not to.
Many people believe that the New Testament changed the commandments around this, but if you study those passages you will see that the foundational dietary principles of Scripture that were outlined in Leviticus 11 remain unchanged.
Related posts:
Understanding 1 Corinthians 10:27
Four Distinctions We Need to Make to Understand Scripture
Peter's Vision Was About People - Not What We Eat