I like the point about three kinds of legalism, from R C Sproul, Jnr, as reported by Stacy McDonald.
Legalism is a loaded word; but, as far as I can tell, there are three ways it is used, two are legitimate usages and one is just handy for shutting someone down. All Fred has to do when losing a debate on a biblical topic is accuse you of legalism and the conversation is closed. With fear and trembling, many back off—and Fred is the winner. Or is he?
Still, true legalism is a thing to detest. The two following definitions are what I would call the real McCoy:
Grace Plus Nothing
The first form of legalism is the ugliest because it attempts to usurp the very Grace of God. Most of us will agree on this one. Anything that adds works to our salvation is legalism. There is nothing we can do to earn God’s favor. Without Christ we are totally depraved, totally helpless, and totally in need of a Savior. Our “good works” are as filthy rags and we can’t do anything to earn our salvation—He did it all. I didn’t find Jesus; He found me, kicking and screaming.
Holier Than Jesus
The second form of legalism has to do with adding rules to God’s laws (Col. 2:20-22). I have found this to be what most people are referring to when they talk about legalism. Sometimes this type of legalism is simply a matter of misinterpreting the Scriptures. Other times it is an issue of pride. Usually, it’s a poor attempt at holiness—trying to do things in our own strength and in our own wisdom, rather than in God’s.
There are indeed precious souls who are bound up in false teachings that keep them from living the full life that God intended. But will we ever all agree on what is legalism and what is part of living a godly life? I doubt it.
John doesn’t believe in celebrating Christmas, but he enjoys a glass of wine with dinner. His friend, Carl, believes alcohol consumption, even in moderation is wrong, but he has the most beautiful Christmas tree you’ve ever seen.
Jennifer believes in adhering to Old Testament dietary restrictions, but feels the freedom to wear modest pants. Her sister-in-law would never put on a pair or pants, but she thinks Jennifer is being legalistic about not eating pork.
Depending upon who you talk to, any of these things (and plenty more) may be labeled as legalistic.
All things are lawful for me, but not all things are helpful; all things are lawful for me, but not all things edify. Let no one seek his own, but each one the other’s well-being. (1 Corinthians 10:23-24)
It’s that “putting others first” thing again. Discussing, studying, and sharing our various ideas and views is healthy and good. Iron sharpens iron as we are all learning and growing, but we must be so careful of the way we treat one another—being forbearing with one another’s weaknesses and faults.
The False “Legalist” Label
The third form of legalism is imaginary. If you believe in living according to God’s Word, you better be prepared for false accusations of legalism from someone, somewhere, at some time. Growing Antinomianism (anti-law) in our culture has escalated such accusations.
"Yes, and all who desire to live godly in Christ Jesus will suffer persecution." (2 Timothy 3:12)
Even when you seek to obey God in faith because you love Him (not because you’re attempting to earn his favor) those looking in from the outside may make assumptions about you—especially if they are convicted by your lifestyle and unwilling to evaluate their own lives.
Calling others legalistic based on outward appearance is itself legalistic and hypocritical. Some of those who say that they have left legalism have really just exchanged one form for another and are still judging the spirituality of others based on how they are perceived by the ex-legalist.
Our works don’t save us – our faith in Jesus does. But if we are in Christ, we must walk in those good works (prepared ahead of time by Him) for the glory of God. It's what we were created for.