Question: "What does the Bible say about legalism? How can a Christian avoid falling into the trap of legalism?"
Answer: 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).
Even true believers can be legalistic. We are instructed, rather, to be gracious to one another: "Accept him whose faith is weak, without passing judgment on disputable matters" (Romans 14:1). Sadly, there are those who feel so strongly about non-essential doctrines that they will run others out of their fellowship, not even allowing the expression of another viewpoint. That, too, is legalism. Many legalistic believers today make the error of demanding unqualified adherence to their own biblical interpretations and even to their own traditions. For example, there are those who feel that to be spiritual one must simply avoid tobacco, alcoholic beverages, dancing, movies, etc. The truth is that avoiding these things is no guarantee of spirituality.
The apostle Paul warns us of legalism in Colossians 2:20-23: "Since you died with Christ to the basic principles of this world, why, as though you still belonged to it, do you submit to its rules: "Do not handle! Do not taste! Do not touch!"? These are all destined to perish with use, because they are based on human commands and teachings. Such regulations indeed have an appearance of wisdom, with their self-imposed worship, their false humility and their harsh treatment of the body, but they lack any value in restraining sensual indulgence." Legalists may appear to be righteous and spiritual, but legalism ultimately fails to accomplish God's purposes because it is an outward performance instead of an inward change.
To avoid falling into the trap of legalism, we can start by holding fast to the words of the apostle John, "For the law was given through Moses; grace and truth came through Jesus Christ" (John 1:17) and remembering to be gracious, especially to our brothers and sisters in Christ. "Who are you to judge someone else's servant? To his own master he stands or falls. And he will stand, for the Lord is able to make him stand" (Romans 14:4). "You, then, why do you judge your brother? Or why do you look down on your brother? For we will all stand before God's judgment seat" (Romans 14:10).
A word of caution is necessary here. While we need to be gracious to one another and tolerant of disagreement over disputable matters, we cannot accept heresy. We are exhorted to contend for the faith that was once for all entrusted to the saints (Jude 3). If we remember these guidelines and apply them in love and mercy, we will be safe from both legalism and heresy. "Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world" (1 John 4:1).