From the time of Christ's Resurrection until today, there have been Gentiles (non-Jewish unbelievers in Jesus), Jews (Jewish unbelievers in Jesus), and born again members of the Body of Christ known as Christians (NOTE: Not all who profess to be Christians are legitimate children of God - Heb. 12:6-8). During the Dispensation of Grace, or the Church Age, the Church is not required to circumcise males, to eat a kosher diet (Acts 15:5-24), or to celebrate the Sabbath (Col. 2:16).
You will note that nearly all of the material in the Gospels of the New Testament presents the life of Jesus, and that the Gospels end with His death, burial, and resurrection. Because of Daniel 9:24-27, we know that the material addressing His life to the time He was crucified, fits within the first sixty-nine weeks (actually periods of seven yrs. each, or 483 yrs.). Christ offered Himself as their Messiah (Dan. 9:24; Jn. 1:11), and they rejected Him. Therefore, the Gospels were written primarily to the Jews.
And while the Gospels are filled with references to the Law of Moses, the Book of Acts through the first three chapters of Revelation consistently speak of salvation being a gift of Grace through faith in Christ. That material applies to the mysterious parenthetical period between the sixty-ninth week and the seventieth week of Daniel's prophecy, which we know as the Church Age (Eph. 5:32). Daniel's Seventieth Week is also known as The Tribulation, and The time of Jacob's Trouble, (Dan. 9:27; Jer. 30:7; Matt. 24:3-29; Rev. 4 - 18).
I have said all that to point out the fact that a believer should not view the entire Bible as being applicable to his or her walk with the Lord. Promises made to Abraham do not necessarily apply to the Church. The attitudes of the Old Testament writers often fail to harmonize with that of Jesus. Christians don't pray for fire to come down from heaven to destroy our enemies, or for bears to eat their children. We are commanded to love our enemies, and pray for them.
Yes, "All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness" (2 Tim. 3;16). But a faithful workman who is led to preach, must rightly divide the Word of God. He needs to ask: 1) To whom is the passage written? 2) Did the passage address a specific time and situation? 3) Was there a principle given that applies to all believers throughout time? 4) Does my interpretation of the passage fit into the overall teaching of God's Word? The whole counsel of God is to be preached throughout the world, but it needs to be preached correctly. There is enough confusion and division already. God bless you as you "study to shew thyself approved."