Wells Marsh said in post 19:
John 1:17 For the law was given through Moses, but grace and truth came through Jesus Christ.
Amen.
On Jesus' cross, for both Jews and Gentiles (Jn. 11:51-52), of all times, the letter of the Old Covenant Mosaic law (the OCML) was disannulled (Heb. 7:18-19), abolished (Eph. 2:15-16, Col. 2:14-17, 2 Cor. 3:6-18), rendered obsolete (Heb. 8:13, Gal. 3:2-25, 4:21-5:8), taken away and replaced (Heb. 10:9) by the better hope (Heb. 7:19), the better covenant (Heb. 7:22, 8:6-12), the second covenant (Heb. 8:7, 10:9), of Jesus' New Covenant law (Gal. 6:2, Jn. 1:17, Mt. 26:28, Heb. 12:24, 9:15), so that the law was changed (Heb. 7:12). All believers, both Jews and Gentles, of all times, are delivered from the letter of the OCML and shouldn't keep it (Rom. 7:6, 2 Cor. 3:6-18, Gal. 2:11-21) or have any desire to keep it (Gal. 4:21-5:8, 3:2-25). Believers keep the spirit of the OCML (Rom. 7:6) by loving others (Gal. 5:14, Rom. 13:8-10), by doing to others as they would have others do to them (Mt. 7:12).
The New Covenant is a new law (Heb. 7:12,18-19, 10:1-23), consisting of Jesus' New Testament commandments (Jn. 14:15), such as those he gave in the Sermon on the Mount (Mt. 5:19-7:29) and in the epistles of Paul the apostle (1 Cor. 14:37). These commandments exceed in righteousness the abolished letter of the OCML (Mt. 5:20-48), so that there's no reason why any believer should ever want to go back under the letter of the OCML (Gal. 3:2-5:26). It was just a temporary schoolmaster (Gal. 3:24-25), a temporary shadow (Col. 2:16-17), which God set up because of sins long after he had set up the original promise of the Abrahamic Covenant and long before he brought that promise to fulfillment in Jesus' New Covenant (Gal. 3:16-29, Mt. 26:28). The letter of the OCML has been made obsolete by the New Covenant (the NC) (Heb. 8:13). For example, the letter of the OCML required an Aaronic priesthood (Ex. 30:30), whereas the NC replaced the Aaronic priesthood with the Melchisedechian priesthood (Heb. 7:11-28). And the letter of the OCML required animal sacrifices (e.g. Lev. 23:19), whereas the NC replaced those with the one-time sacrifice of Jesus (Heb. 10).
The letter of the OCML is the Hagar to the NC's Sarah (Gal. 4:22-25), so that those people, whether Jews or Gentiles, who try to keep the letter of the OCML are like Ishmael, while those people, whether Jews or Gentiles, who keep the NC are like Isaac (Gal. 4:22-31). The letter of the OCML (including the letter of the ten commandments), written and engraven in stones (2 Cor. 3:7, Deut. 4:13, 27:8), was the ministration of death and condemnation (2 Cor. 3:7,9; e.g. Lev. 20:10, Ex. 31:14, Num. 15:32-36; contrast the NC's Jn. 8:4-11, Mt. 12:1-8) which has been done away (2 Cor. 3:11), abolished (2 Cor. 3:13b), yet it's still able to spiritually blind some people as with a veil from beholding Jesus (2 Cor. 3:14-16), whereas the NC is the ministration of the spirit and righteousness (2 Cor. 3:6,8,9b) which remains (2 Cor. 3:11b) and which permits believers to remove the veil and to behold Jesus (2 Cor. 3:16-18, Mk. 15:38, Heb. 7:18-19, Eph. 2:15-18, Col. 2:14-17).
But a mistaken spirit of Pharisaism is still able to deceive even some believers into thinking that they must still keep the letter of the OCML in order to be saved (Acts 15:1,5), or in order to become perfect (Gal. 3:2-5:26). This is a false, cursed gospel (Gal. 1:6-9), for if any believers are keeping any part of the letter of the OCML, thinking they must do so in order to be saved, or in order to become perfect, then they have fallen from grace (Gal. 5:2-8).