Law of Christ
The majority Christian theology, known as supersessionism, states that this either "replaces" or "completes" or "fulfills" the previous Law of Moses of the Hebrew Bible. Dual-covenant theologians are an example of a group that reject this belief.
The law of Christ in the Pauline epistles 
In the Epistle to the Galatians, written by Paul of Tarsus to a number of early Christian communities in the Roman province of Galatia in central Anatolia, he wrote: "Bear one another's burdens, and so fulfill the law of Christ." (Galatians 6:2, NKJV). This could be an allusion either to the Second greatest commandment ("love thy neighbor") or the New Commandment ("love one another").
Possibly related, in a letter to the early Christians of Corinth, Greece, in the First Epistle to the Corinthians, Paul wrote: "To those not having the law I became like one not having the law (though I am not free from God's law but am under Christ's law), so as to win those not having the law." (1 Corinthians 9:21, NIV).
It is not clear exactly what Paul means by the phrase, "the law of Christ". Although Paul mentions Biblical law several times (e.g., Romans 2:12–16, 3:31, 7:12, 8:7–8, Galatians 5:3, Acts 24:14, 25:8) and preached about Ten Commandment topics such as idolatry (e.g., 1 Corinthians 5:11, 6:9–10, 10:7, 10:14, Galatians 5:19–21, Ephesians 5:5, Colossians 3:5, Acts 17:16–21, 19:23–41), he consistently denies that salvation, or justification before God, is based on "works of the law" (e.g., Galatians 3:6-14), though the meaning of this phrase is also disputed by scholars, see for example the New Perspective on Paul#Works of the Law.
Commandments of Christ in the gospels 
Many Christians believe that the Sermon on the Mount is a form of commentary on the Ten Commandments. It portrays Christ as the true interpreter of the Mosaic Law. In the Expounding of the Law, Jesus said that he did not come to abolish the law or the prophets, but to fulfill them (Matthew 5:17). In the apocryphal Gospel of Marcion's version of Luke 23:2 we find the extension: "We found this fellow perverting the nation and destroying the law and the prophets".
While the New Testament records several unique sayings of Jesus that may be described as "commandments," it only records one that he explicitly identified as such. This is the New Commandment of John 13:34-35 that the disciples should love one another as he himself had loved them.
These commandments are commonly seen as a basis of Christian ethics.
New Testament law in the Epistle of James 
Related to the concept of the law of Christ and so-called "New Testament law", James 2:8-13 uses the phrases of "royal law" and "law of liberty" in reference to the Second greatest commandment, part of Leviticus 19:18:
|“||You shall love your neighbor as yourself.||”|
Referenced views of the meaning of the phrase 
In his Summa Theologiae I-II qq. 106-109, Saint Thomas Aquinas discusses the Law of Christ as the "New Law". He argues that it was virtually contained in the Old Law, that is the Old Testament, as a seed but only brought to perfection by Jesus Christ who perfectly fulfilled it. The ends of the Old and New are one and the same, being subjection to God's order, but they are different in that the New Law makes the attaining the end possible. Meanwhile, since all law ultimately has reference to Divine Reason governing all things, the New Law contains and helps the human being fulfill the Natural Law which prescribes acts of virtue. Thus, Aquinas defines the New Law as "chiefly the grace itself of the Holy Ghost, which is given to those who believe in Christ," but adds that it also "contains certain things that dispose us to receive the grace of the Holy Ghost, and pertaining to the use of that grace." Therefore,"the New Law is in the first place a law that is inscribed on our hearts, but that secondarily it is a written law".(ST I-II q. 106.3)
See also 
- Biblical law in Christianity
- Council of Jerusalem
- Cafeteria Christianity
- Evangelical counsels
- Law and Gospel
- The New Commandment
- Pauline Christianity
- Red-Letter Christian
- Sermon on the Mount
- Such as Hebrews 8:6 etc. See also Catholic Encyclopedia: Epistle to the Hebrews: "The central thought of the entire Epistle is the doctrine of the Person of Christ and His Divine mediatorial office. ... There He now exercises forever His priestly office of mediator as our Advocate with the Father (vii, 24 sq.)."
- "Sermon on the Mount." Cross, F. L., ed. The Oxford dictionary of the Christian church. New York: Oxford University Press. 2005
- Ante-Nicene Fathers: Tertullian: Against Marcion: Dr. Holmes' Note: "In [Luke 23:2], after the words "perverting the nation," Marcion added, "and destroying the law and the prophets; Gospel of Marcion: Jesus Before Pilate and Herod
- BERNARD HÄRING, The Law of Christ, I, translated by Edwin G. Kaiser, Cork 1963, introduction.
- Five views on Law and Gospel, Gundry ed., an online copy at DJMOO.COM, Page 368: "Love is central to this law, and there is strong continuity with the law of Moses, for many specifically Mosaic commandments are taken up and included within this "law of Christ"." Page 370: "Indeed, we can confidently expect that everything within the Mosaic law that reflected God's "eternal moral will" for his people is caught up into and repeated in the "law of Christ." Having recognized the place within "the law of Christ" of specific commandments, however, I want to insist that they must not be given too much prominence." Page 376: "The content of all but one of the Ten Commandments is taken up into "the law of Christ", for which we are responsible. (The exception is the Sabbath commandment, one that Heb. 3-4 suggests is fulfilled in the new age as a whole.)"
- George R. Law, “The Form of the New Covenant in Matthew,” American Theological Inquiry 5:2 (2012).