1 Corinthians 10 teaches us that all things are lawful, and we should use all things to the advantage of others and not ourselves.
Paul said "All things are lawful, but not all things are helpful. All things are lawful, but not all things build up." We should use all things for the good of others, to lift up one another and edify the Body of Christ.
No one should seek for their own good, but the good of their neighbor. As Christians, we lift our neighbor up above ourselves.
Paul was not even concerned about meats offered unto idols, even though it was against the law of the old covenant. He said to eat whatever is sold in the meat market without raising any concerns or questioning with our conscience. The earth is the Lord's and the fullness thereof!
We are to be careful what things we partake in when in the presence of unbelievers. Those who do not know Christ and hang on to the old laws are not aware that all things are lawful. Paul said that if we are invited to eat with an unbeliever and they tell us the meal had been offered in sacrifice, for their sake we should stop eating. Since they do not know Christ, they will think we have sinned before God. Paul said we should not partake for their conscience, not for our own.
We should also be free to partake in all things. Paul asked, "Why should my liberty be determined by someone else's conscience? If I partake with thankfulness, why am I denounced because of that for which I give thanks?"
All things lawful are not only limited to food. Paul said "whatever we eat or drink, or whatever we do." But, we should do these things all to the glory of God. We should give offense to no one. Everything we do should be to lift up another, seeking their advantage so that they also might be saved.
As Christians, we should ask ourselves: Do we place our neighbor before ourself? Do we do all things to lift up one another and lead them to salvation? Are we robbed of our glory by letting our liberty be determined by someone else's conscience? Are we Christians or do we remain bound to the law that Christ came to fulfill?