Abraham married his sister, a fact your seem to want to avoid. However, Abraham believed God.
Romans 3:27-31
Where is boasting then? It is excluded. By what law? Of works? No, but by the law of faith. 28 Therefore we conclude that a man is justified by faith apart from the deeds of the law. 29 Or is He the God of the Jews only? Is He not also the God of the Gentiles? Yes, of the Gentiles also, 30 since there is one God who will justify the circumcised by faith and the uncircumcised through faith. 31 Do we then make void the law through faith? Certainly not! On the contrary, we establish the law.
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Romans 9:30-33
What shall we say then? That Gentiles, who did not pursue righteousness, have attained to righteousness, even the righteousness of faith; 31 but Israel, pursuing the law of righteousness, has not attained to the law of righteousness. 32 Why? Because they did not seek it by faith, but as it were, by the works of the law. For they stumbled at that stumbling stone. 33 As it is written:
"Behold, I lay in Zion a stumbling stone and rock of offense,
And whoever believes on Him will not be put to shame."
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Galatians 2:14-16
14 But when I saw that they were not straightforward about the truth of the gospel, I said to Peter before them all,"If you, being a Jew, live in the manner of Gentiles and not as the Jews, why do you compel Gentiles to live as Jews? 15 We who are Jews by nature, and not sinners of the Gentiles, 16 knowing that a man is not justified by the works of the law but by faith in Jesus Christ, even we have believed in Christ Jesus, that we might be justified by faith in Christ and not by the works of the law; for by the works of the law no flesh shall be justified.
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Galatians 3:1-7
O foolish Galatians! Who has bewitched you that you should not obey the truth, before whose eyes Jesus Christ was clearly portrayed among you as crucified? 2 This only I want to learn from you: Did you receive the Spirit by the works of the law, or by the hearing of faith? 3 Are you so foolish? Having begun in the Spirit, are you now being made perfect by the flesh? 4 Have you suffered so many things in vain -- if indeed it was in vain?
5 Therefore He who supplies the Spirit to you and works miracles among you, does He do it by the works of the law, or by the hearing of faith? -- 6 just as Abraham "believed God, and it was accounted to him for righteousness."
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Galatians 3:10-12
For as many as are of the works of the law are under the curse; for it is written, "Cursed is everyone who does not continue in all things which are written in the book of the law, to do them." 11 But that no one is justified by the law in the sight of God is evident, for "the just shall live by faith." 12 Yet the law is not of faith, but "the man who does them shall live by them."
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In Galatians 3:10 Paul quotes Deuteronomy:
Deuteronomy 27:26 'Cursed is the one who does not confirm all the words of this law.'
"And all the people shall say, 'Amen!'"
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Now, what have you done? You have posted that the sacrificial and convictions of the Law are no longer applicable and by doing so have not confirmed all the words of this law. On the other hand Paul confirmed the whole Law is good including the dietary laws, the sacrificial laws as well the laws concerning convictions, but cannot save anyone.
Tell us mdibbits, where does faith enter into your theology? Faith in Jesus Christ precludes works of the Law as the path to living a righteous life. In fact no man can attain righteousness apart from the grace of God. Abraham who committed incest with Sarah believed God and God counted his faith as righteousness. Peter tells us that Lot who committed incest with his daughters is righteous.
Romans 1:16-17
16 For I am not ashamed of the gospel, for it is the power of God for salvation to everyone who believes, to the Jew first and also to the Greek. 17 For in it the righteousness of God is revealed from faith to faith; as it is written, "But the righteous man shall live by faith."
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Galatians 2:20-21
20 "I have been crucified with Christ; and it is no longer I who live, but Christ lives in me; and the life which I now live in the flesh I live by faith in the Son of God, who loved me, and delivered Himself up for me. 21 "I do not nullify the grace of God; for if righteousness comes through the Law, then Christ died needlessly."
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Galatians 3:10-14
11 Now that no one is justified by the Law before God is evident; for, " The righteous man shall live by faith. " 12 However, the Law is not of faith; on the contrary, "He who practices them shall live by them." 13 Christ redeemed us from the curse of the Law, having become a curse for us-- for it is written, "Cursed is everyone who hangs on a tree"-- 14 in order that in Christ Jesus the blessing of Abraham might come to the Gentiles, so that we might receive the promise of the Spirit through faith.
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Man does not obtain salvation by works of the Law plus faith, which is what you believe and teach. Man obtains salvation by God's grace through faith in Jesus Christ apart from the Law, which is why the Holy Spirit inspired the Council of Jerusalem to write:
Acts 15:23-29
23 They wrote this, letter by them:
The apostles, the elders, and the brethren,
To the brethren who are of the Gentiles in Antioch, Syria, and Cilicia:
Greetings.
24 Since we have heard that some who went out from us have troubled you with words, unsettling your souls, saying, "You must be circumcised and keep the law" -- to whom we gave no such commandment -- 25 it seemed good to us, being assembled with one accord, to send chosen men to you with our beloved Barnabas and Paul, 26 men who have risked their lives for the name of our Lord Jesus Christ. 27 We have therefore sent Judas and Silas, who will also report the same things by word of mouth. 28 For it seemed good to the Holy Spirit, and to us, to lay upon you no greater burden than these necessary things: 29 that you abstain from things offered to idols, from blood, from things strangled, and from sexual immorality. If you keep yourselves from these, you will do well.
Farewell.
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You seem to have a fixation on sexual immorality, which is covered in verse 29. You have been blinded by men teaching a gospel other than that preached by Jesus and his apostles, a gospel based on the rhetoric of men and not in faith. Paul addressed men like you and apparently your pastor:
Galatians 1:8-9
8 But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed. 9 As we have said before, so now I say again, if anyone preaches any other gospel to you than what you have received, let him be accursed.
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I pity you and those like you because you fear God's judgment and have chosen to ignore this:
1st John 4:18-19
18 There is no fear in love; but perfect love casts out fear, because fear involves torment. But he who fears has not been made perfect in love. 19 We love Him because He first loved us.
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