Recently over at the Internet Monk, there was a discussion on how to live as a Christian in the midst of legalistic churches. That's a sticky question on all sorts of levels. First, we have to define what "legalism" is. I would say that any church or person who puts more faith in works, or what your deeds are, to get you into heaven than in the atoning sacrifice of Jesus is legalistic. This is doubly true if the deeds that are emphasized are not deeds mentioned in the Bible as being problem areas. If there is any sort of a Checklist of Salvation the chances are pretty good it's legalism. And we are not under the law but under grace.
Shall we sin so that grace may abound? Ahhh, yeah. That part. The most common response to legalism is to go hard the other way and essentially state that there are no rules. Jesus loves you even when you're banging the neighbor's wife and anybody that says otherwise is being judgmental. The war cry for these folks is two fold. The aforementioned "under grace" line and the ever popular "Judge not lest ye be judged." In my experience everyone who has said "Judge not" while discussing sin and the repentance from sin, is currently doing some thing that violates their conscious but would rather ignore it than repent.
Jesus talks about how to properly, and lovingly, correct someone and, if they refuse it, to kick them out of the church. Paul, who stresses unity above almost everything, still says there are times when a person needs to be asked to leave. He even cites a couple of cases. What's this got to do with legalism? Simply, there ARE some "rules" that one needs to follow if he/she expects to remain in the fellowship. Jesus didn't just say "give me your burdens". He also said to take his up. Carry your cross daily. James said faith without works is dead. It's impossible to read the NT and not come away with the idea that if you do indeed believe in Jesus, there will be things you do, and don't do, because of it.
The big danger here for churches and church leaders is knowing what to expect from the congregation. Quite simply, if the Bible doesn't forbid it expressly, I think it's best to leave that up to Christian Conscious. Drinking alcohol is nowhere forbidden in the Bible. Therefore to preach that it is sin to EVERYONE is wrong. Are there those in your church to whom drinking is a sin because God and their conscious has deemed it so? Yes. And your job as a brother or sister is not to drink around them, not to tell stories involving a good drink etc. around them and to encourage them in their own walk. If it's too big of a sacrifice to go out to eat at Perkin's instead of Applebee's when they're with you, maybe you need to examine your own heart. The same is true if they insist that nobody, EVER has a drink.
There are any number of things clearly spelled out in the Bible as "sin". Lying, gossiping, sex outside of marriage, unforgiveness, irrational anger at somebody are among them. If somebody in your church is doing these things, it is our responsibility to bring them up. Not in a finger pointing, AH-HA!!, sort of way but in love, like the way you would tell your children not to play touch football on the four lane street. On the flip side, these things can not be allowed to fester and grow in the church. If the person continues to resist the correction both Jesus and Paul say to kick them out of the body. Like a cancer needs to be cut out before it kills you, people sinning unrepentantly need to be removed from the church body before it catches on.
It's a fine line. Separating the two takes a lot of prayer and a lot of time in the Bible. I was once told "Stupid rules get made because people do stupid things." This is true. It is also how legalism gets started, with the best of intentions to help someone you love. Soon, what started out as a temporary request becomes doctrine that must not be violated.