Why should Christians reject legalism?

Legalism detracts from the grace of God by imposing rules and regulations that cannot bring about true righteousness or salvation. As Paul points out in Galatians 2:4-5, he did not yield to the legalistic demands placed upon believers, advocating instead for the freedom found in Christ. Legalism breeds spiritual slavery, creating a burden that neither the forefathers nor believers can bear (Acts 15:10). The essence of the gospel is that salvation comes through faith in Christ alone, and any attempt to add to that through human effort undermines the very foundation of grace. Thus, Christians are called to stand firm in their liberty and reject any teachings that seek to add to the simplicity of the gospel.