To prompt your thinking on this subject, I will quote a few Scriptures that capture my point. In Paul’s first letter, he warns about “having begun” our Christian walk “by the Spirit”, but now seeking to be “perfected by the flesh” (Galatians 3:3). This is the opposite of the gospel of grace. This principle is so critical that Paul continues in chapter 5:1, “For freedom Christ has set us free; stand firm therefore, and do not submit to a yoke of slavery.”
Legalism is very deceptive because it makes us think that we are more acceptable to God by following a set of made-man rules that appear to be righteousness, but miss the grace of God in Christ. False teachers are famous for alluring their audiences into following a certain “form or appearance of godliness, but deny its power.” Paul exhorts to “avoid such people” (2 Timothy 3:5)
Notice how jealous Paul was of the pure work of grace in believers: “For I feel a divine jealousy for you, since I betrothed you to one husband, to present you as a pure virgin to Christ. But I am afraid that as the serpent deceived Eve by his cunning, your thoughts will be led astray from a sincere and pure devotion to Christ.” (2 Corinthians 11:2–3). Any purpose other than “pure devotion to Christ” will lead you into bondage and steal your freedom in Christ. BE CAREFUL of this danger!