Mosaic Law - Law of God vs Law of Christ

From ESV Study Bible

Heb. 8:13 The new covenant makes the first one old (Gk. palaioō, here translated obsolete)—so old that it is becoming like a person of extreme age (Gk. gēraskō, here translated growing old) and thus is near to disappearing (ready to vanish away).

1 Tim. 1:9–11 the law is not laid down for the just. People who are “just” do not need the law to restrain them, but those who are lawless and disobedient need such restraint. Paul is not denying that the law has a use in teaching Christians how to live, for he has said it is “good” (v. 8) and in vv. 9–10 he echoes several of the Ten Commandments (Ex. 20:1–17), in their OT order. Exactly how the law applies to the NT believer is a matter of some debate. Some argue that the Mosaic law has been entirely superseded, and what remains is the “Law of Christ” (see note on 1 Cor. 9:21). Others argue for an abiding authority of certain aspects of the Mosaic code. Paul elsewhere affirms that Christians are no longer under the Mosaic law (see Rom. 7:6; Gal. 2:16; 3:19–26), and that fits well with what he writes here. As in those other passages, these verses indicate that one purpose of the law is to expose sin. In addition, though believers are no longer under the Law of Moses, they are, as noted, under the Law of Christ and are governed by the Spirit (Rom. 7:6). All interpreters agree that the Mosaic laws, rightly understood, still give Christians wisdom about the kind of conduct that pleases or displeases God. See notes on 1 Cor. 9:21; Gal. 4:10; 5:14; 6:2.

1 Cor. 9:21 those outside the law. Outside the Mosaic law, which defined the Jewish way of life. not . . . outside the law of God . . . the law of Christ. Paul seems to distinguish between the Jewish law and something he calls alternately “the commandments of God” (cf. 7:19) and “the law of Christ,” which is of continuing validity for Christians, whatever their ethnicity. This second law appears to include the ethical teaching of Jesus as well as absorbing both the theological structure and many of the moral precepts of the Mosaic law. (See, e.g., Rom. 7:7, 12, 22; 13:8–10; Gal. 5:14; 6:2; Eph. 6:2; see also the articles on Biblical Ethics.) This “law of Christ” today would also include the moral commands of the NT epistles, since in them the apostles interpreted and applied Christ's life and teachings to the NT churches