Even though it is true that doers of the law are justified by the law, there is no one justified other than Jesus that was actually justified by the law so, you are a hearer of the law only, because you failed to do it, and you can't use Jesus as an excuse for a "do over." On the other hand, I'm a doer of the word (the promise). That is, I believe it! And receive my inheritance without the requirement to do the law, the avenue you'd rather take to obtain your inheritance, which only ONE has ever done.
For if the inheritance depends on the law, then it no longer depends on a promise; but God freely granted it to Abraham through a promise.-Galatians 3:18
While we do not earn the promise as the result of having first obeyed God's law, that does not mean that the obedience to God's law is not central to the content of what the promise is in regard to.
In Matthew 4:15-23, Jesus began his ministry with the Gospel message to repent for the Kingdom of God is at hand, which was a light to the Gentiles, and God's law was how his audience knew what sin is (Romans 3:20), so repenting from our disobedience to it is a central part of the Gospel message, which is in accordance with Jesus being sent to bless us in fulfillment of the promise by turning us from our wickedness, which was the Gospel that was made known in advance to Abraham in accordance with the promise (Galatians 3:8), which he preached to Gentiles in Haran in accordance with the promise (Genesis 12:1-5).
In Genesis 18:19, God knew Abraham that he would teach His children and those of his household to walk in His way by doing righteousness and justice that the Lord may bring to Abraham all that He has promised. In Genesis 26:4-5, God will multiply Abraham's children as the starts in the heaven, to his children He will give all of these lands, and through his children all of the nations of the earth will be blessed because he heard God's voice and guarded His charge, His commandments, His statutes, and His laws. In Deuteronomy 30:16, if the children of Abraham will love God with all of their heart by walking in His way in obedience to His commandments, statutes, and laws, then they will live and multiply and God will bless them in the land that they go to possess. So the promise was made to Abraham and brought about because he walked in God's way in obedience to His law, he taught his children and those of his house hold to do that in accordance with spreading the Gospel, and because they did that.
In John 8:39, Jesus said that if they were children of Abraham, then they would be doing the same works as him, and in Psalms 119:1-3, God's law was how the children of Abraham knew how to be blessed by walking in God's way, so the way that the children of Abraham are multiplied and are a blessing to the nations in accordance with inheriting the promise through faith is by teaching the nations to turn from their wickedness and to do the same works as Abraham by walking in God's way in obedience to His law in accordance with spreading the Gospel.
There are many verses that describe God's law as being His instructions for how to walk in His way, such as Deuteronomy 10:12-13, 1 Kings 2:1-3, Joshua 22:5, Isaiah 2:2-3, Psalms 103:7, and many others.
If you're a doer of the law, you're not a doer of the word.
God's law is God's word, so your statement is contradictory.