Well, that’s a good question! The question could also be asked another way: what makes a person want to be, or remain a legalist? This, essentially, was the question recently posed by a friend on Facebook. Assuming we know what a legalist is, what makes a person attracted to this way of thinking? Let me respond with five possible answers.
But before we go any further, let’s make sure we’re on the same page. What is a legalist? Here are a couple of really good, all-around definitions of legalism. The first one is from GotQuestions.org (which I recommend). I would advise reading the whole piece on their website. The following is an excerpt:
The word “legalism” does not occur in the Bible. It is a term Christians use to describe a doctrinal position emphasizing a system of rules and regulations for achieving both salvation and spiritual growth. Legalists believe in and demand a strict literal adherence to rules and regulations. Doctrinally, it is a position essentially opposed to grace. Those who hold a legalistic position often fail to see the real purpose for law, especially the purpose of the Old Testament law of Moses, which is to be our “schoolmaster” or “tutor” to bring us to Christ (Galatians 3:24). http://www.gotquestions.org/Bible-Christian-legalism.html
The second is a definition found on Wikipedia. Believe it or not, it is a pretty in-depth article. Again, here is a portion of that article:
Legalism, in Christian theology, is a sometimes-pejorative term referring to an over-emphasis on discipline of conduct, or legal ideas, usually implying an allegation of misguided rigour, pride, superficiality, the neglect of mercy, and ignorance of the grace of God or emphasizing the letter of law over the spirit. Legalism is alleged against any view that obedience to law, not faith in God’s grace, is the pre-eminent principle of redemption…Legalism refers to any doctrine which states salvation comes strictly from adherence to the law. It can be thought of as a works-based religion. – http://en.wikipedia.org/wiki/Legalism_(theology)
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But to be fair, most people that I would label “legalists” are not people who believe that salvation is earned by works of any kind, at least if they are Baptists. The vast majority of legalists to which I refer, and of which I used to belong, use a system of rules and regulations to determine spirituality, spiritual growth, and favor with God and other believers. They believe, as a whole, in the redemptive work of the cross, but set a universal standard which defines holiness for all who claim Christ, regardless of cultural or societal considerations. To the legalist, anyone who behaves or believes differently than the legalist’s perceived standards must not be “right with God.”
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So, back to the original question:
“Why are Some People Legalists?”
One reason could simply be that they do not know any different.
When I was growing up, I did not know anything different than what I was exposed to in our little churches, missionary conferences, revivals, or Christian schools. Even though I believe that most of what I was taught was doctrinally sound, I was not encouraged to examine different viewpoints, even those of other Baptists, specifically if they were anything other than “Independent, Fundamental, etc.” I was not allowed to explore the true nature of a life of grace and freedom. Many are still in this situation. Tragically, they are content with their ignorance. They refuse to consider the fact that they may be wrong on a particular point. Even when Scripture is plain and simple, because of the secluded nature of these groups, they would rather stick their heads in the sand than risk being wrong. Being wrong might make someone else, even another denomination, right about something. Heaven help us!
A second reason could be that they came from an unholy lifestyle and now seek to redeem themselves (or their consciences).
Some people are so ashamed of their past that they go overboard in trying to live a life of holiness. They see in their past a link between so-called “worldly activities” and their fall into depravity. In an effort to show they are no longer the person they used to be, and in order 
to avoid temptation, they strictly avoid certain activities deemed “worldly.” Sadly, even though they mean well, they project their own weaknesses onto others, therefore expecting others to abide by the same level of austere living, or be seen as worldly. However, in many cases, appearances are not what they seem. The very ones who are so legalistic in some areas of life wind up being the ones with the biggest weakness in that area. Their overbearing attitudes, in many cases, may only be the big doors hiding skeletons in their closet.
A third reason could be the desire to be controlled or told what to do.
As strange as it may sound, some people don’t like to think for themselves, nor do they like being responsible for their own choices. It is sort of like people whom I have seen that were once under a totalitarian government. When they no longer 
had a dictatorial system telling them what to do, they either lost all control or had no motivation to do any good. Legalistic churches provide the lazy or immature Christian a list of “do’s and don’ts” so that he/she doesn’t have to search the Scripture for guidance. It is much easier this way. If the pastor says something is wrong, and that God would not approve, then that’s it – end of discussion. Having a list is safe and doesn’t require much thought. They prefer being a marionette to being mature.
A fourth reason, which is among the more sinister, is that they want to control others.
Freedom is dangerous. Freedom allows for movement and change. Freedom allows for the individual to be led by God in a specific 
direction that may or may not be God’s will for another. Freedom takes power away from those who would want to control others for their own edification or gratification. Legalism keeps the sheep under strict control by encouraging tattling and fear of being ostracized. There are pastors, well-intended men, who would rather their people live under a specific set of guidelines than question long-held, man-made traditions. These leaders are afraid to lose their congregations to the world, but also to other churches. They may even find comfort in controlling others due to their own inadequacies. Much like emperors and dictators, they manipulate weak Christians in order to maintain their little kingdoms. Rarely do they admit weakness. Often, they micro-manage every aspect of ministry. They have to be in control.
A fifth reason could be that some people are more afraid of God than in love with Him.
So many people that I know and used to be like were more afraid of losing their relational standing with God than anything else. As a matter of fact, by being legalistic, one could be assured that God was pleased with him. I wonder how it really was for Enoch as he walked with God. Many modern preachers are quick to make the application of Enoch’s walk with God to the way we act in this world. 
They make little of the relationship implied by the narrative (Genesis 5:24). In reality, very few lists would even be needed if one had an abiding relationship with Jesus Christ. To the legalist, God is not a friend; He doesn’t laugh; He speaks in Old English, and He holds a grudge because of what it took to buy the sinner’s salvation. When you think of God as always looking for an opportunity to send judgment, then being legalistic is the safest way to go. You’d hate to be hit with a lightning bolt.
There you have it. I am sure there may be other reasons, but this is a good start.
A lady we know heard of our trip to the tree house. She said she had been there, so I asked her what she thought. “It was all a bunch of nothing,” she said coarsely. She couldn’t understand why anyone would build such a thing, much less visit it. She saw no value in what Mr. Burgess was doing.
The Recovering Legalist 