The Gryphon quoted a website in post #114:
The Mosaic Law is still mandatory for all Jews who have not yet accepted Christ as their Messiah.
Note that it isn't, as far as God is concerned. For on Jesus Christ's Cross, for both Jews and Gentiles (John 11:51-52) of all times, the letter of the Old Covenant Mosaic law was completely and forever abolished (Ephesians 2:15-16, Colossians 2:14-17; 2 Corinthians 3:6-18), disannulled (Hebrews 7:18), rendered obsolete (Hebrews 8:13, Galatians 3:2-25, Galatians 4:21 to 5:8), taken away and replaced (Hebrews 10:9) by the better hope (Hebrews 7:19), the better covenant (Hebrews 7:22, Hebrews 8:6-12), the second covenant (Hebrews 8:7, Hebrews 10:9), of Jesus' New Covenant law (Galatians 6:2, John 1:17, Matthew 26:28, Hebrews 12:24, Hebrews 9:15), so that the law was changed (Hebrews 7:12).
All Christians, whether Jews or Gentles, of all times, are delivered from the letter of the Old Covenant Mosaic law and should not keep it (Romans 7:6; 2 Corinthians 3:6-18, Galatians 2:11-21), or have any desire to keep it (Galatians 4:21 to 5:8, Galatians 3:2-25). Christians keep the spirit of the Old Covenant Mosaic law (Romans 7:6) by loving others (Galatians 5:14, Romans 13:8-10), by doing to others as they would have others do to them (Matthew 7:12).
The New Covenant is a new law (Hebrews 7:12,18-19, Hebrews 10:1-23), consisting of Jesus Christ's New Covenant/New Testament commandments (John 14:15), such as those which He gave in the Sermon on the Mount (Matthew 5:19 to 7:29), and in the epistles of the apostle Paul (1 Corinthians 14:37). These commandments exceed in righteousness the abolished letter of the Old Covenant Mosaic law (Matthew 5:20-48). So there is no reason for any Christian to ever want to go back under the letter of the Old Covenant Mosaic law (Galatians 3:2 to 5:26). It was just a temporary schoolmaster (Galatians 3:24-25), a temporary shadow (Colossians 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 this promise to fulfillment in Jesus' New Covenant (Galatians 3:16-29, Matthew 26:28).
The letter of the Old Covenant Mosaic law has been made obsolete by the New Covenant (Hebrews 8:13). For example, the letter of the Old Covenant Mosaic law required an Aaronic priesthood (Exodus 30:30), whereas the New Covenant replaced the Aaronic priesthood with the Melchisedechian priesthood (Hebrews 7:11-28). And the letter of the Old Covenant Mosaic law required animal sacrifices for sin (Leviticus 23:19), whereas the New Covenant replaced these with the one-time sacrifice of Jesus Christ Himself on the Cross (Hebrews 10).
The letter of the Old Covenant Mosaic law is the Hagar to the New Covenant's Sarah (Galatians 4:21-25). So those people, whether Jews or Gentiles, who try to keep the letter of the Old Covenant Mosaic law are like Ishmael, Abraham's son by a bondmaid (Galatians 4:22), who was cast out (Galatians 4:30), while those people, whether Jews or Gentiles, who keep the New Covenant are like Isaac (Galatians 4:28), Abraham's son by a freewoman (Galatians 4:22,31), who became his heir (Galatians 4:30b).
The Gryphon quoted a website in post #114:
[Re: Jews]
Jesus did what they could not do—fulfill the Law in all its details (Matthew 5:17).
Matthew 5:17-18 means that Jesus Christ came the first time not to abolish the prophecies in the Mosaic law and the Old Testament prophets regarding the Messiah's/the Christ's first coming, but to fulfill all those prophecies (Luke 24:44-48; e.g. Acts 3:22-26, Isaiah 53). Matthew 5:17-18 cannot mean that Jesus came not to abolish the letter of the commandments of the Old Covenant Mosaic law, for He did come to do that, on the Cross (Ephesians 2:15-16, Colossians 2:14-17, Romans 7:6; 2 Corinthians 3:6-18, Hebrews 7:18-19). Also, Matthew 5:17-18 cannot mean that Jesus came to fulfill the letter of all of the Old Covenant Mosaic law's commandments, for He could not possibly have done that. For example, some of those commandments applied only to women after childbirth (Leviticus 12:4-8), or to wives suspected of adultery by their husbands (Numbers 5:19-31).
As the Christ (Matthew 5:17, Luke 24:44-46), the mediator of the New Covenant (Matthew 26:28, Hebrews 12:24, Hebrews 7:22, Hebrews 8:6-9), Jesus had the divine authority to contradict the letter of the Old Covenant Mosaic law's commandments and replace them with His own, even better, New Covenant commandments (Matthew 5:38-44, Matthew 19:7-9, John 8:5-7), such as those He gave in the Sermon on the Mount (Matthew 5:19 to 7:29) and in the epistles of the apostle Paul (1 Corinthians 14:37; 1 Thessalonians 4:2). And as the Christ, Jesus had the divine authority to allow His disciples to break the letter of the Old Covenant Mosaic law's commandments (Matthew 12:1-8).
The Gryphon quoted a website in post #114:
The Church does not replace Israel . . .
That's right.
For even though the Church is Israel (Revelation 21:9,12; 1 Peter 2:9-10), the Church does not "replace" Israel, because Gentiles in the Church are grafted in by God to become only parts of an already-existing Israel (Romans 11:17,24, Ephesians 2:12,19, Galatians 3:29, John 10:16), which includes the Jews in the Church (Romans 11:1).
The Gryphon quoted a website in post #114:
As one reads Scripture, it is necessary to keep Israel and the Church separate.
Note that just as the Gentile Ruth (a genetic forbear of Israel's Messiah: Matthew 1:5-16, Luke 3:23-32) could say to the Israelite Naomi: "thy people shall be my people, and thy God my God" (Ruth 1:16), so Gentiles in the Church have been grafted into Israel (Romans 11:17,24, Ephesians 2:12,19, Galatians 3:29).
That is, all Jews in the Church remain members of whichever tribe of Israel they were born into (Romans 11:1, Acts 4:36). And all Gentiles in the Church have been grafted by God into Israel (Romans 11:17,24, Ephesians 2:12,19, Galatians 3:29), and so have been grafted by God into its various tribes (cf. Ezekiel 47:21-23). So the entire Church is the twelve tribes of Israel (Revelation 21:9,12; 1 Peter 2:9-10). This is necessary, for all those in the Church are saved only by the New Covenant (Matthew 26:28; 1 Corinthians 11:25; 2 Corinthians 3:6, Hebrews 9:15), which God has made only with Israel (Jeremiah 31:31-34, John 4:22b). John 10:16 refers to the "other sheep" of Gentile Christians being brought into "this fold" of Israel, which is the "one fold" of the Church (1 Corinthians 12:13, Ephesians 4:4-6, Revelation 21:9,12). A Gentile Christian can pray and ask which tribe of Israel he has been grafted into by God, and he will receive an answer, if he asks in faith (cf. Matthew 21:22), without any wavering (cf. James 1:6-7).
Also, all those in the Church, whether Jews (Acts 22:3) or Gentiles (Romans 16:4b), have become spiritually-circumcised Jews if they have undergone the spiritual circumcision of water-immersion (burial) baptism into Jesus Christ (Romans 2:29, Philippians 3:3, Colossians 2:11-13).