How do you build

The question arises for the believer on what to do with scriptures when it comes to hearing, listening and obedience. One major component is understanding what you hear and from what source does the 'voice' come from. In Paul's writings, he admonishes the believers to 'take heed on how you build' as the foundation has already been laid (Torah-Old testament) and Messiah Y'Shua (Jesus) being the cornerstone. Having said that, our objective should be to build upon that which was already established up and including Messiah's teachings. Some people would say that it (Torah) is done away with and that the Spirit will lead ME and teach me all I need to know. As we know, Scripture was given by the Almighty's finger during Moses (Moshe) time and since scripture also says, 'He changeth not'.....I would think our starting point (foundation and cornerstone) would be the best place to build upon - carefully. So if someone says to you that they really don't need to heed the (Instructions) of the 'Old' Testament, as they only need the Holy Spirit's guidance.., then Why are we admonished to 'Study to show thyself approved unto Elohim'? I think the written words, the Living Word (Y'Shua), the Ruach (Spirit) and the Father are all ONE (Echad).....so says Scriptures. Amein Baruch Ata Adonai Eloheneu Melech Ha Olam!