From BelieveTheSign

    Legalism, in Christian theology, is the act of putting law above gospel by establishing requirements for salvation beyond repentance and faith in Jesus Christ and reducing the broad, inclusive and general precepts of the Bible to narrow and rigid moral codes.[1] It is an over-emphasis of 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 at the expense of 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 can take different forms:

    1. where a person attempts to keep the Law in order to attain salvation;
    2. where a person keeps the law in order to maintain his salvation; or
    3. when a Christian judges other Christians for not keeping certain codes of conduct that he thinks need to be observed.