Disclaimer: When this article was originally written for Path Treader Ministries, I was still a vegetarian. Though I have since ceased that lifestyle, I have decided to keep the article mostly unchanged, as the point still stands, it just loses a part of its original "kick".
You know the Bible is clear on the issue of food when a vegetarian is willing, and able, to stand up for a Christian's right to eat bacon. I remember one time debating a man on this issue. In his view, Levitical food laws are still in place.
I thought this would have been an easy debate to settle. Romans 14 tells us some people believe they can eat only vegetables, but others believe they can eat all things, and both are right, because in Christianity, the thought really counts. But this person thought "all things" has a limit. 1 Timothy 4, however, calls this a "doctrine of devils".
This man is what the Bible refers to as a "weaker brother". Barring a false conversion, he is still saved. It's just that, for whatever reason, he is personally opposed to eating any food Leviticus declares unclean. This man thinks eating such food is sin, and he is right. For him. “But he who doubts is condemned if he eats, because he does not eat from faith; for whatever is not from faith is sin.” (Romans 14:23). In his weaker faith, this man is genuinely forbidden to eat against Levitical law.
But if you are able to eat with thanksgiving to God, there are no foods the Bible declares unclean to you. You think you can eat bacon? Give thanks to God and you can. It's only in the presence of weaker brothers that such becomes sin, but at that point, it's not the food that is sinful, but the disregard for a fellow Christian's conscience.