In this passage, Paul is specific concerning the losses of a believer who puts themselves back under the law and doesn’t enjoy the Christian freedom that Jesus purchased for them. When we go back to the law method of living our Christian life, we lose instead of gain.
When we place ourselves under the law: We limit, rather than release, God’s work in our life. In V. 1 "entangled" – lit. "to hold in" means to ensnare. "yoke of bondage" – something that binds. It’s not a liberated life, it’s a life of bondage. - It doesn’t free us to become what God wants, it keeps us from becoming what He wants. Let me illustrate how bondage under the Law can be almost synonymous (indicated by the word “again”) with bondage under paganism. Suppose that a European nation was once ruled by a cruel, iron-fisted dictator, then overtaken by Hitler’s Nazi Germany, and later “liberated” by Russian Communism. By whatever name, each regime was merely another form of bondage. Thus, Paul can say that to follow the teaching of the Judaizers was to return “again” to bondage, not precisely the same bondage, but bondage nonetheless. Circumcision is a serious sin because it puts one back under the Law and thus makes righteousness a matter not of faith, but works. A correlation is that the one who is circumcised is thus seeking to establish his righteousness before God by law-keeping and no longer by faith. For this reason Paul can say they have “been severed from Christ” and “have fallen from grace” (v. 4). Circumcision signified a change in the basis of one’s righteousness.
In what area in your life of relationship with God do you seek to establish your righteousness by law-keeping and no longer by faith?